WO1991010459A1

WO1991010459A1 - Hemostasis valve introducer

Info

Publication number: WO1991010459A1
Application number: PCT/US1991/000229
Authority: WO
Inventors: Steven D. Savage; Gregory Brucker
Original assignee: Angeion Corporation
Priority date: 1990-01-10
Filing date: 1991-01-09
Publication date: 1991-07-25

Abstract

A hemostasis valve introducer (10) is used in medical procedures in the vascular system which require multiple insertions of a medical device such as in angioplasty or angiography procedures. A hemostasis valve introducer (10) includes a valve housing (12), a valve member (16) in the valve housing (12), a cap (14) on the proximal end, a sheath (24) at a distal end, and a strain relief (22) which is about the sheath (24) in the valve housing (12). The hemostasis valve introducer (10) utilizes a valve (16) with a reliable seal, lower drag during insertion and retraction, and an enhanced seal over the range of diameters of inserted medical devices. Some of the unique features are the gasket (18) which contains a raised ring (58) on the blood side which provides a circumferential force for sealing around circular devices and for ensuring more rapid and reliable closing of the valve (16) after retraction of the medical device.

Description

HEMOSTASIS VALVE INTRODUCER

CROSS REFERENCES TO CO-PENDING APPLICATIONS This patent application is related to U.S. Patent Application Serial No. 07/362,307, filed June 6, 1989, entitled "Hemostasis Valve Introducer"; and U.S. Patent Application Serial No. 07/372,052, filed June 27, 1989, entitled "Hemostasis Valve Introducer" both to the same assignee as this patent application.

BACKGROUND OF THE INVENTION

1. Field of the Invention - The present invention pertains to a medical, disposable, cardiovascular device, and more particularly, pertains to a hemostasis valve introducer.

2. Description of the Prior Art - The hemostasis valve introducer is used to precutaneously insert a medical device into a vein or an artery. Typically, such introducers contain a one-way check valve which allows introduction of the medical device in the forward direction; that is, into the body, but does not permit the flow of the blood backward; that is, out of the body.

Prior act introducer devices have two main concerns. First, the prior art devices do not reliably seal with multiple insertion and retraction of a medical device either with or without the device in place. Secondly, the prior art introducers have not sealed well with multiple devices in place simultaneously. The main problem with hemostasis valve introducers is the reliability o'f the seal after repeated insertions and retractions of a medical device through the valve and the high drag associated with insertions and retractions of these devices.

Representative U.S. prior art patents include U.S. Patent Nos. 4,000,739 for a hemostasis cannula; 4,143,853 for a valve for use with a catheter; 4,424,833 for a self-sealing gasket assembly; 4,430,081 for a hemostasis sheath; 4,436,519 for a removable hemostasis valve; 4,610,665 for a medical instrument; 4,610,674 for a catheter introducing instrument; 4,626,245 for a hemostasis valve; and, 4,682,981 for a medical device. U.S. Patent No. 4,424,433 is a representative prior art patent.

The present invention overcomes the deficiencies of the prior art introducer devices. The present invention overcomes these disadvantages by using the natural pressure difference that exists between the body and atmospheric pressure to help insure closure of the valve and uses a thickened, raised portion to provide circumferential force for sealing around the invention device while using very thin materials in other regions to provide for a complete seal.

SUMMARY OF THE INVENTION

The general purpose of the present invention is to provide a hemostasis valve introducer for use in medical procedures in the vascular system which reliably seals after repeated insertions of a medical device, which seals with a device in place simultaneously, and which seals more reliably when the device has been removed, especially after multiple insertions.

According to one embodiment of the present invention, there is provided a hemostasis valve introducer including a valve housing member with an internal chamber extending therethrough, a cap with a centered hole at one end of the housing, a self-healing valve about or in the internal chamber, an introducer sheath at the other end of the housing, and a tapered strain relief to prevent kinking of the sheath. Snap connections, threaded connections or ultrasonic welding can secure the components. An access port can extend at an angle from the valve housing member for injection of fluids ^"through the introducer. The valve includes a conical cross section with the core towards the body and a raised ring on the blood side. An optional slit can be provided between the inner diameter points of said ring.

Significant aspects and features of the present invention include a hemostasis valve introducer which reliably seals with multiple insertions and retractions, and which can accommodate a device a substantial period of time and serve rapidly and reliably after the said device is removed.

Additional significant aspects and features of the present invention is a valve for a hemostasis valve introducer which is of lower drag during insertion and retraction; more reliably seals after multiple insertions and retractions; provides for a conical entry angle for introduction of the device which allows for smoother entry of the medical device; and a single valve design so that the valve can be easily fabricated using standard molding and assembly techniques.

Having thus described principal embodiments of the present invention, it is the principal object hereof to provide a hemostasis valve introducer.

One object of the present invention is a valve for a hemostasis valve introducer using a conical cross section where the higher pressure difference on the blood side causes the gasket to be forced against itself and, thus, seal along the slit or line of entry through the gasket. The raised portion is approximately .038 in diameter and .010 of an inch thick and this provides circumferential force to seal around devices less than .038 of an inch. For devices larger than this, the natural expansion and elasticity of the gasket will provide an adequate seal. By incorporating both of these mechanisms into the valve structure, the other regions of the valve can be made very thin, and as a result, the combination of these features and the thin gasket provides a valve with a much lower drag.

BRIEF DESCRIPTION OF THE DRAWINGS

Other objects of the present invention and many of the attendant advantages of the present invention will be • readily appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings, in which like reference numerals designate like parts throughout the figures thereof and wherein:

FIG. 1 illustrates a perspective view of a hemostasis valve introducer;

FIG. 2 illustrates a cross-sectional view of the valve;

FIG. 3 illustrates a bottom view of the valve;

FIG. 4 illustrates a top view of the valve;

FIG. 5 illustrates an exploded view in cross section of the hemostasis valve introducer;

FIG. 6 illustrates a side exploded view of the elements of the hemostasis valve introducer; and,

FIG. 7 illustrates a cross-sectional view of the elements of the hemostasis valve introducer as assembled.

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 illustrates a perspective view of a hemostasis valve introducer 10 of the present invention including a valve housing member 12 with a central body, an internal geometrically configured chamber, and an interlocking interface on each end as illustrated in FIG. 2. A valve 16 engages about or in the chamber area, and is retained therein by cap 14 as later described in detail in FIG. 2. A tapered strain relief 22 engages about the valve housing central body member 12, and assists in supporting a sheath 24 within the chamber. An optional access port 26 extends outwardly from the valve housing 12. The sheath 24 is tapered at its most distal point to allow for ease of insertion into the body. The components can be mechanically snapped together, mechanically threaded together, ultrasonically welded together, or secured together by any other type of suitable securing materials such as glue or adhesive.

FIG. 2 illustrates a cross-sectional view of the valve 16 including a rim 50, conical cross section 52 with a cone 54 pointed towards the body. A raised ring 58 extends about a truncated top 56 of the cone 54. A cylindrical recess 60 with a base 62 is formed into the truncated top 56. A slit 64 extends between the beak of the cone 54 and the base 62 of the cylindrical recess 60. For hemostasis valve introducers capable of holding medical devices in the size range, 5 Fr - 9 Fr, the valve 16 has a diameter of .250 inches and a thickness ranging from 0.015 to 0.065 with the thickness depending on the size of the device to be inserted. The angle of entry on the internal cone can vary from 60 to 80 degrees which again depends on the size of the device to be inserted. The angle on the external portion of the cone can vary from 70 to 90 degrees; thus providing a thicker cross section near the edges and a thinner cross section near the center. Another feature called a raised ring has a thickness of approximately .020 of an inch and has its inner edge on a diameter of .035 inches from about the center of the gasket. The diameter of the raised ring is determined by the size of the guidewire to be inserted into the hemostasis valve introducer, which typically for cardiovascular procedures is 0.35 to 0.38 inches. Contained within the raised circle is the slit 64 which passes through the center ^"point of the valve and extends across the diameter of the area contained within the raised circle. This slit 64 provides a structure for devices to be inserted through the valve 16. The additional benefit of the raised ring is that it acts as a reinforcement to prevent significant tearing of the gasket when devices are in place; especially those of a larger size. Typically, the valve is made of elastomeric materials, such as silicone, natural rubber or thermoplastic elastomers (TPE) . FIG. 3 illustrates a bottom view of the valve 16 where all numerals correspond to those elements previously described.

FIG. 4 illustrates a top view of the valve 16 where all numerals correspond to those elements previously described.

FIG. 5 illustrates an exploded view in cross section of the hemostasis valve introducer 10 along line 2-2 of FIG. 1 where all numerals correspond to those elements previously described. The valve housing central body member 12 includes an internal chamber area 28, an interlocking section 34 on the valve body, and a slot 31 which engages mating ridge 35 of the sheath 24, preserving the through hole luminal diameter 37. The external distal end of the valve housing central body member 12 engagingly interlocks at interlocking section 34 to e₄ngage with mating section 33 of the supporting strain relief 22 at the proximal end 22a. The distal tip of the sheath 24a is tapered to provide for ease of insertion. The cap 14 includes a mating section 44 for engaging with the interlocking section 36. The cap 14 sandwiches the valve 16 between the interior surface of the cap and the proximal end of the valve housing central body member 12. The valve housing central body member 12 also includes an annular surface 39 which mates to the optional support gasket 18. The cap 14 includes an access port 46 through the substantially planar surface 48 of the cap 14. The optional access port 26 extends vertically from the valve housing central body member 12 and includes an orifice 38 therein with tube engaging surfaces.

FIG. 6 illustrates a side exploded view of the elements where all numerals correspond to those elements previously described.

FIG. 7 illustrates a cross-sectional view of the elements assembled where all numerals correspond to those elements previously described.

MODE OF OPERATION

When there is no insertion device present in the hemostasis valve introducer 10, the valve is sufficiently thick to create a seal between blood pressure of the body and the outside environment. When an insertion device is present in the hemostasis valve introducer, the insertion device deforms the valve and the valve takes the shape of the inserted device engaging closely around the inserted device, preventing leakage. Upon removal of the inserted device, the valve moves back together returning to its original position, sealing against loss of blood or body fluids. The elastomeric nature of the material, the conical shape of the gasket, the raised ring, and the pressure difference across the valve all serve to reliably and repeatably return the gasket to its original and sealed configuration.

A typical hemostasis valve introducer has three differing geometrical configurations, namely, large medical device in place, small medical device in place, and no device in place. With a large device inserted into the valve which is defined as a device which is greater than the inner diameter of the thickened ring, the valve stretches using its natural elasticity, and is firmly drawn around the device by the circumferential tension ,'created in the elastomeric material. The raised ring section of the valve_^prevents the slit from further tearing into a much larger slit and relieving the circumferential tension in the material, and thus, potentially creating a leak. With a smaller device in place, less than the diameter of the ring, the raised ring provides a circumferential support area which basically allows the much larger valve to act as a very small valve whose diameter is that of the inner circle. The raised ring provides support such that a thin material contained within the ring does not deform greatly; thus, creating a leak around the device. By having circumferential support, the slit is forced to remain in essentially parallel plane and to deform around the circular device rather than splitting into a crack which would permit loss of blood. With no device in place, the conical nature of the valve utilizes the pressure difference which exists between the body and the ambient pressure and by nature of being higher on the external side of the valve creates compressive forces within the gasket; thus, forcing the slit together and permitting a better seal under the positive action of the pressure. By having this added force of the pressure difference which exists, in addition to the elastomeric forces within the valve, a more positive and reliable seal is obtained especially after multiple insertions and retractions of medical devices in a vascular environment. The present invention utilizes the natural pressure difference that exists between the body and atmospheric pressure to help insure closure of the valve and uses a thickened, raised portion to provide circumferential force for sealing around the device while using very thin materials in other regions to provide for a complete seal. By using a conical cross section, the higher pressure difference on the blood side causes the valve to be forced against itself, and thus, seal along the slit or line of entry through the gasket. The raised portion is approximately .038 in diameter and .020 of an inch thick, and this provides circumferential force to seal around devices less than .038 of an inch. For devices larger than this, the natural expansion and elasticity of the valve will provide an adequate seal. By incorporating both feature mechanisms in the valve, the other regions of the valve can be made very thin, and as a result, the combination of these features and the thin valve provides a valve with a much lower drag. A typical hemostasis valve introducer is used to introduce a catheter into a blood vessel or any other such medical device into the body. In a typical cardiology procedure, this is performed by first piercing a blood vessel with a Seldinger needle, that is, a needle with a hollow center. Next a guidewire is inserted into the blood vessel by passing it through the internal lumen of the Seldinger needle. The needle is then withdrawn leaving a guidewire in place. Next the dilator is inserted into the introducer and the entire dilator sheath assembly passed over the guidewire. The dilator initially enlarges the blood vessel providing adequate space for the sheath. The guidewire and dilator are then withdrawn, leaving the introducer in the bloodstream. The higher pressure of the body is contained by the hemostasis valve, thus preventing loss of blood or fluids.

Various modifications can be made to the present invention without departing from the apparent scope hereof.

WE CLAIM:

Claims

1. A valve for a hemostasis valve introducer comprising: a. a rim member; b. an inner conical cross section within said rim member and including a truncated top; and, c. a raised ring about said truncated top.

2. A valve for a hemostasis valve introducer comprising: a. a rim member; b. an inner conical section within said rim member and including a truncated top; c. a cylindrical recess extending into said truncated top; d. a ring on said truncated top and surrounding said cylindrical recess; and, e. a cut slit extending between a bottom of said cylindrical recess and said conical section.

3. Hemostasis valve introducer for a vascular system comprising: a. valve housing with a valve body therein and including a sheath extending outwardly therefrom for insertion in the vascular system; b. a ringed valve means in said valve housing; and, c. a cap retaining said valve member in said valve body.

4. In combination, a valve in a hemostasis valve introducer comprising: a. a valve for a hemostasis valve introducer including rim member, an inner conical section within said rim member and including a truncated top, a cylindrical recess extending into said truncated top, a ring on said truncated top and surrounding said cylindrical recess, and a cut slit extending between a bottom of said cylindrical recess and said conical section; and, b. valve housing with a valve body therein including a sheath extending outwardly therefrom and including an access port at a right angle thereto, said valve in said valve housing, and a cap retaining said valve member and said support gaskets in and about said valve body.