Peel-away hemostasis valve

Abstract

To provide systems and methods for realizing a peel-away hemostasis valve.SOLUTION: A hemostasis valve body provides strong sealing around a medical device during insertion of the medical device into a blood vessel, low forces for tearing, and stability during insertion of the medical devices and during peel-away. The valve body comprises a first surface, a second surface opposite the first surface, an edge, helical slits, and a pair of longitudinal cuts. The helical slits are positioned at a center of the valve body and traverse from the first surface to the second surface. The helical slits provide a seal around the medical device. Each longitudinal cut extends from the first surface partially through the valve body to a depth short of the second surface for at least part of a length of the longitudinal cut. The longitudinal cuts facilitate a separation of the valve body into two parts during a peel-away action.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims the benefit of U.S. Provisional Patent Application No. 62 / 582,075, filed November 6, 2017, the entire contents of which are incorporated herein by reference.

[0002] FIELD OF THE INVENTION The present disclosure relates to systems and methods for achieving a peel-away hemostatic valve. [Background technology]

[0003] background Introducer sheaths are used to percutaneously insert medical devices, such as heart pumps, guidewires, and diagnostic catheters, into a patient's arteries or veins. The hemostatic valve and hub are part of the introducer sheath and are designed to allow the medical device to be inserted through them and to be removable in-line from the inserted medical device. During insertion of the medical device, the hemostatic valve should resist tearing while maintaining hemostasis. Additionally, the hemostatic valve may separate into two pieces with an acceptable force during the peel-away operation of the introducer sheath.

[0004] Some peel-away hemostatic valve designs have a thickness that aids in sealing but requires a large tear force. Other peel-away hemostatic valve designs are cut through the entire thickness of the valve body to reduce tear force, but make it difficult to seal around the medical device used throughout the procedure. However, many current peel-away hemostatic valves do not exhibit the performance required to insert modern heart pump systems.

[0005] In addition to sealing performance and ease of stripping, a hemostatic valve should also provide stability during insertion of a heart pump system and during stripping. Some peel-away hemostatic valve designs suffer from double break during stripping, which occurs when the valve has two distinct points of resistance to tearing. For example, the double break points may be located near the edge of the valve and in the center of the valve. Double break can cause movement while the heart pump system is within a patient's artery or vein and can cause damage to the patient's arteriotomy and / or the heart pump system. A need exists for a hemostatic valve design that mitigates double break during stripping and improves the stability of heart pump system placement during the procedure. Summary of the Invention

[0006] The systems, methods, and devices described herein enable peel-away hemostatic valves designed in a manner to reduce tearing force, provide a strong seal around a medical device, and provide stability during insertion and peel-off of the medical device. The valves of the present disclosure have a longitudinal cut defined by a cylindrical surface axially aligned with the outer diameter of the hemostatic valve and an edge aligned with the helical trajectory of one of the helical slits in the center of the hemostatic valve. Compared to existing valves, the design of the longitudinal cut in the valve of the present disclosure reduces the force required to tear the peel-away hemostatic valve from end to end during a peel-off operation. The longitudinal cut and the helical slit are separated by a fixed distance across the thickness of the valve, which provides better hemostatic performance compared to hemostatic valves with longitudinal cuts throughout the valve. The peel-away hemostatic valve of the present disclosure also has a through-hole along its periphery; the through-hole facilitates connecting the hemostatic valve to the hub of the introducer and (when a post is inserted in the through-hole) maintains extension of the hemostatic valve during the peel-away action.

[0007] Disclosed herein are embodiments of a hemostatic valve body having a first surface, a second surface opposite the first surface, a rim, a helical slit, and a pair of longitudinal cuts. The rim extends between the outer periphery of the first surface and the outer periphery of the second surface. The helical slit is positioned in the center of the valve body and traverses from the first surface to the second surface. The helical slit provides a seal around a medical device during insertion of the medical device into a blood vessel. Each respective longitudinal cut extends from the first surface partially through the valve body for at least a portion of the length of the respective longitudinal cut to a depth that does not reach the second surface. The longitudinal cuts facilitate separation of the valve body into two portions during a peel-away operation. Disclosed herein are embodiments of a peel-away hemostatic valve that seals well against a medical device inserted therein and also allows the hemostatic valve to be peeled away with little force. Additionally, the peel-away hemostatic valve design of the present invention prevents double tearing and enhances the stability of the medical device or heart pump system during the procedure.

[0008] In certain embodiments, the longitudinal cuts may be positioned a distance from the helical slits. In some embodiments, the longitudinal cuts may be angled similarly to the angle of rotation of the helical slits. In certain embodiments, each respective longitudinal cut may be positioned on an opposite side of the valve body. In some embodiments, each respective longitudinal cut may traverse from the first surface to the second surface near an edge for at least a portion of the length of the respective longitudinal cut.

[0009] In one embodiment, the hemostatic valve body may include first lines formed on a first surface and second lines formed on a second surface. The first lines may extend radially outward from a center of the valve. The second lines may extend radially outward from a center of the valve. In some embodiments, a helical slit may traverse from the first lines to the second lines. In some embodiments, the first lines may be angularly offset from the second lines.

[0010] In certain embodiments, the hemostasis valve body may include a through-hole traversing from the first surface to the second surface at a distance from the edge. In some embodiments, each respective through-hole may include one of a rounded edge, a flat edge, and an asymmetrical shape. In some embodiments, the through-holes may be angularly equally spaced. In certain embodiments, the angle between adjacent through-holes may be equal to or less than 25 degrees. In other embodiments, the through-holes may be sized to accommodate a port. In some embodiments, the through-holes may hold the hemostasis valve body in tension during a stripping operation (when a post is inserted therethrough).

[0011] In one embodiment, the first surface may be parallel to the second surface. In some embodiments, the first surface and the second surface may have a planar shape. In some embodiments, the first surface may have one of a conical shape, a tapered shape, and a convex shape. In certain embodiments, a shallow point of the first surface may be at the center of the valve.

[0012] In some embodiments, the valve body may have a disk shape. In one embodiment, the valve body may have one of a cylindrical shape and a cubic shape.

[0013] In a further embodiment of the present disclosure, a system for inserting a blood pump into a patient's blood vessel is provided. The system includes the blood pump and an introducer assembly including a sheath and a hub including a hemostatic valve body. The sheath and hemostatic valve body may be sized to receive the blood pump. The introducer hub includes wings and notches that facilitate breaking of the introducer hub. To break the introducer hub during a stripping operation, a medical professional applies force to the wings. The notches are intentionally implemented as weak points on the hub that break when sufficient force is applied to the wings. A longitudinal cut on the hemostatic valve body may be radially aligned with the notches so that the valve breaks without significant force along the longitudinal cut.

[0014] In a further embodiment of the present disclosure, a method is provided for stripping an introducer sheath assembly having: (1) an introducer hub having (a) first and second wings positioned opposite one another and (b) first and second notches positioned midway between the first and second wings; (2) a hemostatic valve within the introducer hub having first and second longitudinal cuts radially aligned with the first and second notches; and (3) an introducer sheath having longitudinal scoring aligned with the first and second notches. As described above, the wings and notches facilitate fracture of the introducer hub. Compared to other stripping methods, this method achieves smooth stripping along a consistent tear path by aligning intentionally implemented points of weakness on the introducer hub, hemostatic valve, and introducer sheath. The method includes applying a first force to a first wing of the introducer hub in a first direction radially from the introducer sheath and applying a second force to a second wing of the introducer hub in a second direction opposite the first direction. The method further includes transmitting the first and second forces to first and second notches in the introducer hub, thereby rupturing the first and second notches. The method further includes rupturing the hemostatic valve along the first and second longitudinal cuts. The method further includes separating the introducer sheath along the longitudinal scoring. [The present invention 1001] a first surface and a second surface opposite the first surface; an edge extending between an outer periphery of the first surface and an outer periphery of the second surface; a plurality of helical slits in the center of the valve body traversing from the first surface to the second surface, the helical slits providing a seal around the medical device during insertion of the medical device into a blood vessel; and a pair of longitudinal cuts, each extending from the first surface partially through the valve body to a depth that does not reach the second surface for at least a portion of the length of the respective longitudinal cut, the longitudinal cuts facilitating separation of the valve body into two portions during a stripping operation; A hemostasis valve body comprising: [The present invention 1002] A hemostatic valve body of the present invention 1001, wherein the longitudinal cut is positioned at a distance from the helical slit. [The present invention 1003] The hemostatic valve body of any of the present inventions 1001 and 1002, wherein the longitudinal cut is angled at the same angle as the rotation angle of the helical slit. [The present invention 1004] A hemostatic valve body according to any one of the present inventions 1001 to 1003, wherein each respective longitudinal cut is positioned on an opposite side of the valve body. [The present invention 1005] A hemostatic valve body according to any one of claims 1001 to 1004, wherein each respective longitudinal cut traverses from the first surface to the second surface near the edge for at least a portion of the length of the respective longitudinal cut. [The present invention 1006] first lines formed on the first surface extending radially outward from the center of the valve; and second lines formed on the second surface extending radially outward from the center of the valve; The hemostasis valve body of any one of the present inventions 1001 to 1005 further comprises: [The present invention 1007] The hemostatic valve body of the present invention 1006, wherein the plurality of helical slits extend from the first group of lines to the second group of lines. [The present invention 1008] The hemostasis valve body of either of the present inventions 1006 and 1007, wherein the first group of lines are angularly offset from the second group of lines. [The present invention 1009] The hemostasis valve body of any one of inventions 1001 to 1008, further comprising a plurality of through-holes traversing from the first surface to the second surface at a distance from the edge. [The present invention 1010] The hemostasis valve body of the present invention 1009, wherein each respective through-hole has one of a rounded edge, a flat edge, and an asymmetrical shape. [The present invention 1011] The hemostasis valve body of any of the present inventions 1009 and 1010, wherein at least some of the plurality of through-holes are angularly equally spaced. [The present invention 1012] A hemostatic valve body of the present invention 1011, wherein the angle between adjacent through-holes is equal to or less than 25 degrees. [The present invention 1013] A hemostasis valve body according to any one of claims 1009 to 1012, wherein the plurality of through-holes are sized to accommodate a plurality of posts of an introducer hub. [The present invention 1014] The hemostasis valve body of the present invention 1013, wherein the plurality of posts are inserted into the plurality of through-holes. [The present invention 1015] The hemostasis valve body of the present invention 1014, wherein the inserted posts keep the hemostasis valve body in tension during the stripping action. [The present invention 1016] The hemostasis valve body of any one of the present inventions 1001 to 1015, wherein the first surface is parallel to the second surface. [The present invention 1017] A hemostasis valve body according to any one of the present inventions 1001 to 1016, wherein the first surface and the second surface have a planar shape. [The present invention 1018] The hemostasis valve body of any one of inventions 1001 to 1015, wherein the first surface has one of a conical shape, a tapered shape, and a convex shape. [The present invention 1019] The hemostatic valve body of any one of inventions 1001 to 1018, wherein the shallow point on the first surface is at the center of the valve. [The present invention 1020] A hemostatic valve body according to any one of claims 1001 to 1019, having one of a disk shape, a cylindrical shape, and a cubic shape. [The present invention 1021] blood pumps; and An introducer assembly comprising a hub and a sheath, wherein the hub comprises a hemostasis valve body according to any one of claims 1001 to 1020, and the hemostasis valve body and the sheath are sized to receive the blood pump. 1. A system for inserting a blood pump into a patient's blood vessel, comprising: [The present invention 1022] (1) an introducer hub having (a) first and second wings positioned opposite one another, and (b) first and second notches positioned midway between the first and second wings; (2) a hemostatic valve in the introducer hub having first and second longitudinal cuts radially aligned with the first and second notches; and (3) an introducer sheath having longitudinal scoring aligned with the first and second notches; An introducer assembly having 1. A method of stripping a substrate, comprising the steps of: applying a first force to the first wing of the introducer hub in a first direction radially from the introducer sheath and applying a second force to the second wing of the introducer hub in a second direction opposite the first direction; transmitting the first force and the second force to the first and second notches of the introducer hub, thereby breaking the first and second notches; rupturing the hemostatic valve along the first and second longitudinal cuts; and Separating the introducer sheath along the longitudinal scoring. [The present invention 1023] 1. A system for stripping an introducer assembly, the system comprising: means for receiving a first force against a first wing of the introducer hub and a second force against a second wing of the introducer hub; means for transmitting the first force and the second force to the first notch and the second notch of the introducer hub, thereby fracturing the first notch and the second notch; means for rupturing the hemostatic valve of the introducer hub along a first longitudinal cut and a second longitudinal cut on the hemostatic valve, the first longitudinal cut aligned with the first notch on the introducer hub and the second longitudinal cut aligned with the second notch on the introducer hub; and Means for separating the introducer sheath along longitudinal scoring on the introducer sheath, the longitudinal scoring being aligned with the first notch and the second notch. [Brief explanation of the drawings]

[0015] 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.

[0016] [Figure 1] 1 illustrates an exemplary medical device constructed in accordance with one or more aspects of the present disclosure. [Figure 2] 2 illustrates an exemplary introducer inserted into a patient's blood vessel, with the medical device of FIG. 1 extending therethrough, constructed in accordance with one or more aspects of the present disclosure. [Figure 3] 3 illustrates a cross-section of the medical device of FIG. 1 inserted into the peel-away hemostatic valve of the introducer of FIG. 2, constructed according to one or more aspects of the present disclosure. [Figure 4] FIG. 1 is an isometric view of a peel-away hemostatic valve constructed in accordance with one or more aspects of the present disclosure. [Figure 5]FIG. 1 is an isometric view of a peel-away hemostatic valve with hidden lines configured in accordance with one or more aspects of the present disclosure. [Figure 6] FIG. 1 is a bottom view of a peel-away hemostatic valve configured in accordance with one or more aspects of the present disclosure. [Figure 7] FIG. 1 is a top view of a peel-away hemostatic valve configured in accordance with one or more aspects of the present disclosure. [Figure 8] FIG. 1 is a side view of a peel-away hemostatic valve constructed in accordance with one or more aspects of the present disclosure. [Figure 9] FIG. 1 is a top view of an introducer hub configured in accordance with one or more aspects of the present disclosure. [Figure 10] FIG. 1 is an isometric view of an introducer hub configured in accordance with one or more aspects of the present disclosure. [Figure 11] FIG. 1 is a top view of a peel-away hemostatic valve inserted into an introducer hub, configured in accordance with one or more aspects of the present disclosure. [Figure 12] FIG. 1 is an isometric view of a peel-away hemostatic valve inserted into an introducer hub, configured according to one or more aspects of the present disclosure. [Figure 13] 10 is a flow chart for peeling away an introducer having a peel-away hemostatic valve, constructed in accordance with one or more aspects of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0017] Detailed Description A need exists for a peel-away hemostatic valve that provides a good seal and has characteristics that allow the hemostatic valve to be peeled away with less force. The peel-away hemostatic valve described herein achieves this by incorporating a longitudinal cut defined by a cylindrical surface axially aligned with the outer diameter of the hemostatic valve and an edge aligned with the helical trajectory of one of the helical slits in the center of the hemostatic valve. The longitudinal cut design of the present invention reduces the force required to tear the peel-away hemostatic valve end-to-end during the peel-away operation. The longitudinal cut and the helical slit are separated by a fixed distance, which provides better hemostatic performance compared to hemostatic valves that are cut throughout. Additionally, a need exists for a peel-away hemostatic valve that does not suffer from double fracture and that increases the stability of the heart pump system during the procedure. The peel-away hemostatic valve described herein accomplishes this by incorporating holes along the periphery of the hemostatic valve that connect the hemostatic valve to the hub of the introducer and keep the hemostatic valve in tension during peel-away (when a post is inserted through the holes).

[0018] FIG. 1 illustrates an exemplary medical device, such as a blood pump 100, according to certain embodiments. The blood pump 100 may be an intravascular heart pump, a heart pump driven by a flexible shaft and a motor positioned outside the patient's body, a heart pump including an implantable motor, a heart pump with an extendable pump rotor, or any other suitable pump. The blood pump 100 includes a pump handle 110, a pump head 130, a catheter 120 connecting the pump handle 110 to the pump head 130, and a connection hub 160. The catheter 120 is tubular and has a substantially uniform outer diameter 150. The catheter 120 allows electromechanical communication between the pump head 130 and the pump handle 110. The pump handle 110 communicates with control circuitry that allows control of the pump head 130. The pump head 130 contains electromechanical components that allow the device to perform various tasks within the patient's body, such as pumping blood from a location within the body. Pump head 130 has a diameter 140 that is larger than diameter 150 of catheter 120. One example of such a percutaneous pump is the Impella 2.5® system (Abiomed, Inc., Danvers, Massachusetts).

[0019] As shown in FIG. 2 , the blood pump 100 is inserted into a patient's blood vessel 240 using an introducer 200. The introducer 200 includes a hub 210 and an elongated sheath 202. The hub 210 includes a hemostatic valve 300 (described in more detail below) that provides a seal and minimizes fluid loss during insertion of the blood pump 100. The elongated sheath 202 is sized for insertion into the patient's blood vessel 240. The introducer 200 is advanced into the blood vessel 240 through a vascular aperture 250 in the direction indicated by arrow 248, and the blood pump 100 is then inserted through the hub 210 and the elongated sheath 202 and into the blood vessel 240. The blood vessel 240 may be a femoral artery, and the vascular aperture 250 may be an arteriotomy.

[0020] After the blood pump 100 has been advanced through the introducer 200, the introducer 200 may be removed and, in some embodiments, replaced with a device suitable for longer-term use. To remove the introducer 200, a medical professional may grasp the first and second wings 218a and 218b of the hub 210 and, depending on the orientation of the first and second wings 218a and 218b relative to the elongate sheath 202, may apply a force to the wings 218a and 218b either toward the elongate sheath 202 or radially relative to the elongate sheath 202 to urge the first wing 218a toward the second wing 218b. With the wings 218a and 218b oriented as shown in FIG. 2, the medical professional applies a radial force (radial relative to the elongate sheath 202) to the wings 218a and 218b to move them toward each other. The first and second wings 218a and 218b are formed of a rigid material and do not flex when force is applied. Instead, the applied force is transmitted from the wings 218a and 218b to a first notch 214 and a second notch (not shown) on the introducer hub 210. The second notch is located opposite the first notch 214, and both the first notch 214 and the second notch are located midway between the first and second wings 218a and 218b. The minimum thickness at the notches allows the introducer 200 to break at the first notch 214 and the second notch. Longitudinal scoring 222 on the elongate sheath 202 allows the sheath to separate along the length of the elongate sheath, and the hub 210 and elongate sheath 202 may be peeled away into two pieces while leaving the percutaneous pump 100 in place within the blood vessel 240.

[0021] Figure 3 shows a cross section of the blood pump 100 of Figure 1 inserted into the introducer 200 of Figure 2. The hub 210 of the introducer 200 includes a hemostatic valve 300 that provides a seal and minimizes fluid loss during insertion of the blood pump 100. The hemostatic valve 300 illustrated in Figures 4-8 provides a good seal and has features that allow the peel-away hemostatic valve to be peeled away with little force, as described below.

[0022] 4 shows an isometric view of the peel-away hemostatic valve 300. The peel-away hemostatic valve 300 includes a first surface 302, a second surface 304 opposite and parallel to the first surface 302, and an edge 306 extending between the peripheries of the first surface 302 and the second surface 304.

[0023] As shown in FIG. 4 , the peel-away hemostatic valve 300 has a disk shape, with the first and second surfaces 302, 304 being planar and circular and with an edge 306 extending perpendicularly from each of the first and second surfaces 302, 304. In general, the peel-away hemostatic valve 300 may take other shapes, including, but not limited to, a cylindrical or cubic shape. The disk shape may be a subset of a cylinder, with the ratio of the thickness of the edge 306 to the diameter of the first surface 302 being less than 1. In general, the shape of the first and second surfaces 302, 304 may be any suitable shape, such as a triangle, a square, a pentagon, a hexagon, or any other polygon. While the first and second surfaces 302, 304 are illustrated as being planar in FIG. 4 , the surfaces 302, 304 may include any combination of conical, tapered, convex, concave, or flat shapes. Specifically, the thickness 308 of the valve (i.e., the distance between each point on surfaces 302 and 304) may vary throughout the valve body. For example, the valve may be thinnest at the center of the valve such that one or both of surfaces 302 and 304 may include a shallow point at the center.

[0024] The thickness 308 of the peel-away hemostatic valve 300 may be configured to achieve a desired inherent hemostatic performance. The hemostatic performance of the peel-away hemostatic valve is improved when the thickness 308 of the peel-away hemostatic valve 300 is configured to a larger value. In another aspect, the thickness 308 of the peel-away hemostatic valve 300 may be configured to require a specific amount of force during the peel-away action. The amount of force required during the peel-away action is reduced when the thickness 308 of the peel-away hemostatic valve 300 is configured to a smaller value. In some aspects, the thickness 308 of the peel-away hemostatic valve 300 may be configured to achieve a trade-off between the inherent hemostatic performance and the amount of force required during the peel-away action.

[0025] The peel-away hemostatic valve 300 may be inserted into the vasculature by an introducer sheath. The peel-away hemostatic valve 300 may have a medical device inserted therethrough and may be removable in-line from the inserted medical device. The medical device may include a cardiac pump, a guidewire, a diagnostic catheter, a sheath, and a dilator.

[0026] Figure 5 shows an isometric view of peel-away hemostatic valve 300 with hidden dotted lines indicating the cuts present in the valve. Figure 6 shows a bottom view of peel-away hemostatic valve 300. Peel-away hemostatic valve 300 includes through holes 312 positioned along the periphery of the valve, a first set of lines 314 in the center of the valve on the upper surface, a second set of lines 324 in the center of the valve on the lower surface, a helical slit 316 extending through the center of the valve, longitudinal cuts 318a and 318b positioned on opposite sides of the valve and extending away from each other, and through slits 322a and 322b.

[0027] As shown in Figures 5 and 6, the first group of lines 314 is formed on the first surface 302, includes three diametric cuts with the same center, and extends radially outward from the center of the peel-away hemostatic valve 300. The second group of lines 324 is formed on the second surface 304 and has the same shape as the first group of lines 314. The first group of lines 314 and the second group of lines 324 have a snowflake shape. The snowflake shape may have four-fold radial symmetry, six-fold radial symmetry, eight-fold radial symmetry, or any other suitable radial symmetry. The angular offset between the lines in the snowflake shape may be 90°, 60°, 45°, 30°, or any other suitable angle. In another aspect, the snowflake shape may not have radial symmetry.

[0028] A helical slit 316 traverses through the center of the valve from the first group of lines 314 on the first surface 302 to the second group of lines 324 on the second surface 304. The helical slit 316 follows a spiral path between the first surface 302 and the second surface 304. The lengths of the first group of lines 314 and the second group of lines 324 determine the size of the helical slit 316. The size of the helical slit 316 may be set to balance hemostatic performance with the insertion and removal force of a medical device inserted through the peel-away hemostatic valve 300. As the lengths of the first group of lines 314 and the second group of lines 324 increase, the size of the helical slit 316 increases, reducing the hemostatic performance of the peel-away hemostatic valve 300 and reducing the removal force of a medical device inserted through the peel-away hemostatic valve 300.

[0029] Each longitudinal cut 318a and 318b may extend from the first surface 302 partially through the peel-away hemostatic valve 300 to a depth that does not reach the second surface 304 for at least a portion of the length of the respective longitudinal cut 318a or 318b.

[0030] The longitudinal cuts 318a and 318b facilitate separating the peel-away hemostatic valve 300 into two portions during a peel-away operation. The longitudinal cuts 318a and 318b may be positioned a distance from the helical slit 316. Each longitudinal cut 318a and 318b may be positioned on opposite sides of the peel-away hemostatic valve 300. Each longitudinal cut 318a and 318b may traverse from the first surface 302 to the second surface 304 for at least a portion of the length of the respective longitudinal cut 318a or 318b near the edge 306. The region where the longitudinal cut 318a or 318b traverses through the entire thickness 308 of the hemostatic valve 300 is referred to herein as the through slit 322a or 322b; the through slit may serve as an origin for a tear to propagate during a peel-away operation. The longitudinal cuts 318a and 318b in the first surface 302 of the peel-away hemostatic valve 300 may terminate in sharp edges.

[0031] In some embodiments, the longitudinal cuts 318a and 318b are angled similarly to the angle of rotation of the helical slits 316. As shown in FIG. 7 , the angle α of the helical slits 316 defines the angled path the helical slits 316 follow as they traverse the valve 300 from the first surface 302 to the second surface 304. In general, α can be any angle that corresponds to the angular offset between the first set of lines 314 on the first surface 302 and the second set of lines 324 on the second surface 304. In another aspect, the angle α corresponds to the angular offset of two of the helical slits 316 on the first surface 302. In some aspects, α is equal to 360 / n, where n is the number of helical slits 316. In another aspect, α is unrelated to the angular offset of two of the lines 314 on the first surface 302. In this case, α is the helical rotation angle between first and second surfaces 302 and 304 and need not correspond to the angle between the two lines 314; thereby, first set of lines 314 and second set of lines 324 may be angularly offset from one another. As shown in FIG. 8 , angle β of longitudinal cuts 318a and 318b defines the angle between the two faces of each longitudinal cut 318a and 318b. Angles α and β may be related to one another. In some aspects, α and β are within 5%, 10%, or 15% of one another, or any other suitable percentage. In other aspects, α and β are proportional to one another. By aligning the longitudinal cuts 318a and 318b with the helical slit 316 (i.e., by setting α and β such that the faces of the longitudinal cuts 318a and 318b closest to the corresponding cuts in the helical slit 316 follow the path of the corresponding cuts in the helical slit 316), a constant distance is maintained between the longitudinal cuts 318a and 318b and the closest corresponding cuts in the helical slit 316. The constant distance between the longitudinal cuts 318a and 318b and the helical slit 316 may be appropriately set to fine-tune the amount of force required during the stripping operation. If the constant distance between the longitudinal cuts 318a and 318b and the helical slit 316 is set to a high value, a larger force is required during the stripping operation.

[0032] During the peeling action, a tear initiates at the through slits 322a and 322b (located near the valve edge 306) and propagates along a portion of the longitudinal cuts 318a and 318b near the second surface 304. The tear then propagates along the distance between the longitudinal cuts 318a and 318b and the helical slit 166 from the second surface 304 to the first surface 302. The tear propagation results in the separation of the peel-away hemostatic valve 300 into two pieces along the path described.

[0033] In certain embodiments, the peel-away hemostatic valve 300 is partially surrounded by the hub 210 of the introducer 200 (as further described with respect to FIGS. 11 and 12 ) and is aligned with the notches on the hub 210 such that the longitudinal cuts 318 a and 318 b of the peel-away hemostatic valve 300 are aligned with the notches on the hub 210. The alignment of the longitudinal cuts 318 a and 318 b with the notches allows a user to easily separate the peel-away hemostatic valve 300 into two pieces with little force during a peel-away operation using the introducer assembly 200.

[0034] 9 and 10 show top and isometric views, respectively, of the hub 210 of the introducer 200. As shown, the hub 210 has posts 260 arranged in a circular configuration around its periphery and angularly equally spaced apart except for the spacing between the posts 260 closest to the notches in the hub 210. Because the hub 210 breaks along the notches, the angular spacing between the posts 260 closest to the notches in the hub 210 is greater than the spacing between the other posts 260. The posts 260 in the hub 210 extend through through-holes 312 on the valve 300 such that the posts 260 facilitate anchoring and securely securing the valve 300 within the hub 210. The through-holes 312 are located a distance from the edge 306 of the valve and traverse from the first surface 302 to the second surface 304. Although the through-holes 312 shown in Figures 4-7 are circular, each through-hole 312 may include rounded edges, flat edges, or an asymmetrical shape. Figures 11 and 12 show top and isometric views, respectively, of the valve 300 inserted into the hub 210. As shown, the through-holes 312 are angularly aligned with the posts 260 but slightly offset axially. Specifically, the posts 260 have a centerline diameter slightly smaller than the centerline diameter of the through-holes 312. This offset provides the valve 300 with improved inward sealing pressure by keeping the valve in a tensioned state while it is within the hub. In some embodiments, the posts 260 have the same centerline diameter as the centerline diameter of the through-holes 312.

[0035] 11 and 12 ensures that the valve 300 is stretched during the peeling operation, thereby allowing for smooth rupture of the hemostatic valve 300 and preventing double rupture. This is achieved by angularly spacing the thread holes 312 equally apart, except for the spacing between the posts 260 closest to the notch in the hub 210. In some embodiments, the angular spacing is equal to or less than 25 degrees. For a hemostatic valve 300 having an outer diameter equal to or greater than 15 mm and a thread hole 312 diameter equal to or greater than 0.75 mm, the ideal angular spacing of the thread holes 312 is equal to or less than 25 degrees, with equal spacing between the thread holes 312.

[0036] 13 shows a process 1300 for stripping an introducer 200 having (1) an introducer hub 210 having (a) first and second opposite wings 218a and 218b and (b) first and second notches 214 located at the midpoint between the first and second wings 218a and 218b; (2) a peel-away hemostatic valve 300 in the introducer hub 210 having first and second longitudinal cuts 318a and 318b radially aligned with the first and second notches 214; and (3) an introducer sheath 202 having longitudinal scoring 222 aligned with the first and second notches 214. The process 1300 may be used by a medical professional after insertion of a medical device through the introducer 200. In step 1302, a first force is applied to a first wing 218a of the introducer hub 210 in a first direction radial from the introducer sheath 202, and a second force is applied to a second wing 218b of the introducer hub 210 in a second direction opposite the first direction. For example, a medical professional may grasp the first and second wings 218a and 218b of the hub 210 and, depending on the orientation of the first and second wings 218a and 218b relative to the elongate sheath 202, may apply a force to the wings 218a and 218b in either a direction toward the elongate sheath 202 or a direction radially extending away from the elongate sheath 202 to urge the first wing 218a toward the second wing 218b.

[0037] In step 1304, first and second forces are transmitted to the first and second notches 214 of the introducer hub 210, causing the first and second notches 214 to fracture. For example, the applied forces are transmitted from wings 218a and 218b to the first and second notches 214. The minimum thickness at the notches allows the introducer hub 210 to fracture at the first and second notches 214. Additionally, the shape of the notches concentrates stresses to facilitate separation of the hub 210 along the notches. The minimum thickness and shape of the notches provide break walls from which cracks may initiate in the hub 210. In some embodiments, the minimum thickness of the notches ranges from 0.075 mm to 0.35 mm.

[0038] In step 1306, the hemostatic valve 300 of the introducer hub 210 is torn along the first longitudinal cut 318a and the second longitudinal cut 318b. The first longitudinal cut 318a aligns with the first notch 214, and the second longitudinal cut 318b aligns with the second notch. For example, tearing begins at the through-slits 322a and 322b located near the valve edge 306 and at the radial ends of each longitudinal cut 318a and 318b. The tearing then propagates radially inward along portions of the longitudinal cuts 318a and 318b near the second surface 304. As a result, the longitudinal cuts 318a and 318b become complete cuts through the thickness of the valve. At this point, the valve 300 is still intact in the areas between the longitudinal cuts and the helical slits. The tear then propagates through this region between longitudinal cuts 318a and 318b and helical slit 166. Tear propagation in this region may occur in a radial direction, in a direction through the thickness of valve 300, or in a vector with components in both directions. Tear propagation in this region results in separation of peel-away hemostatic valve 300 into two pieces along the path described.

[0039] In step 1308, the introducer sheath 202 separates along the longitudinal scoring 222 on the introducer sheath 202. The longitudinal scoring 222 radially aligns with the first notch 214 and the second notch. For example, the longitudinal scoring 222 on the elongate sheath 202 allows the sheath to separate along the length of the elongate sheath 202, and the hub 210 and elongate sheath 202 are peeled away into two pieces. After the introducer is peeled away, the percutaneous pump 100 is left in place within the blood vessel 240.

[0040] Other objects, advantages, and aspects of various aspects of the present invention will be apparent to those skilled in the art of the present invention and are within the scope of the description herein and the accompanying drawings. For example, but not limited to, structural or functional elements may be rearranged. Similarly, principles based on the present invention may be applied to other examples, and such examples, even if not specifically described herein, are within the scope of the present invention.

Claims

1. a first surface and a second surface opposite the first surface; an edge extending between an outer periphery of the first surface and an outer periphery of the second surface; a plurality of helical slits in the center of the valve body traversing from the first surface to the second surface, the helical slits providing a seal around the medical device during insertion of the medical device into a blood vessel; and a pair of longitudinal cuts, each extending from the first surface partially through the valve body to a depth that does not reach the second surface for at least a portion of the length of the respective longitudinal cut, the longitudinal cuts facilitating separation of the valve body into two portions during a stripping operation; A hemostasis valve body comprising: A hemostasis valve body, wherein each longitudinal cut is spaced from the helical slit such that the inner edge of each longitudinal cut is at a fixed distance from the helical slit closest to the inner edge of the longitudinal cut, and the fixed distance is maintained across a thickness of the hemostasis valve body extending from the first surface to the second surface.

2. 2. The hemostatic valve body of claim 1, wherein the longitudinal cut is angled similarly to the angle of rotation of the helical slit.

3. 3. The hemostasis valve body of claim 1, wherein each respective longitudinal cut is positioned on an opposite side of the valve body.

4. A hemostatic valve body according to any one of claims 1 to 3, wherein each respective longitudinal cut traverses from the first surface to the second surface near the edge for at least a portion of the length of the respective longitudinal cut.

5. first lines formed on the first surface extending radially outward from the center of the valve; and second lines formed on the second surface extending radially outward from the center of the valve; Further comprising: the plurality of helical slits traverse from the first group of lines to the second group of lines; A hemostatic valve body according to any one of claims 1 to 4.

6. The hemostasis valve body of claim 5, wherein the first group of lines are angularly offset from the second group of lines.

7. further comprising a plurality of through holes traversing from the first surface to the second surface at a distance from the edge; The hemostasis valve body of any one of claims 1 to 6, wherein each respective through-hole has one of a rounded edge, a flat edge, and an asymmetrical shape.

8. The hemostasis valve body of claim 7, wherein at least some of the plurality of through-holes are equally angularly spaced.

9. 9. The hemostasis valve body of claim 8, wherein the angle between adjacent through-holes is less than or equal to 25 degrees.

10. The hemostasis valve body of any one of claims 7 to 9, wherein the plurality of through-holes are sized to accommodate a plurality of posts of an introducer hub.

11. The hemostasis valve body of claim 10, wherein the plurality of posts are inserted into the plurality of through-holes.

12. The hemostasis valve body of claim 11 , wherein the inserted posts keep the hemostasis valve body in tension during a stripping operation.

13. The hemostasis valve body of any one of claims 1 to 12, wherein the first surface is parallel to the second surface.

14. The hemostasis valve body of any one of claims 1 to 13, wherein the first surface and the second surface have a planar shape.

15. The hemostasis valve body of any one of claims 1 to 14, wherein the first surface comprises one of a conical shape, a tapered shape, and a convex shape.

16. 16. The hemostatic valve body of any one of claims 1 to 15, wherein the shallow point of the first surface is at the center of the valve.

17. The hemostasis valve body of any one of claims 1 to 16, comprising one of a disk shape, a cylindrical shape, and a cubic shape.

18. blood pumps; and An introducer assembly comprising a hub and a sheath, the hub comprising a hemostasis valve body according to any one of claims 1 to 17, the hemostasis valve body and the sheath being sized to receive the blood pump.

1. A system for inserting a blood pump into a patient's blood vessel, comprising:

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