PRESSURE-SENSING GUIDEWIRE AND SHEATH
A pressure sensing device is provided that can monitor and measure pressure at two points in a vessel or artery without moving the outer sheath or catheter of the device. The outer sheath or catheter includes two spaced apart openings that may be positioned in a vessel or artery on opposing sides of an occlusion. The device also includes an inner elongated tube with at least one opening. The inner elongated tube is slidable with respect to the outer sheath or catheter thereby permitting the opening of the elongated tube to be moved into selective registration with one of the openings of the outer sheath. A pressure measurement may be taken through one of the openings in the outer sheath by aligning the opening of the elongated tube with said opening and, then, a second pressure reading may be taken by sliding the elongated tube within the outer sheath so that the opening of the elongated tube is in registry with the other opening of the tubular sheath. As a result, pressure measurements at two points in a vessel or artery may be taken without moving the outer sheath or catheter.
Latest BOSTON SCIENTIFIC SCIMED, INC. Patents:
The present application is a continuation of U.S. application Ser. No. 14/203,025, filed Mar. 10, 2014, now U.S. Pat. No. 9,113,790 which is a continuation of U.S. application Ser. No. 10/027,154, filed Dec. 20, 2001, now U.S. Pat. No. 8,668,650, the entire disclosures of which are incorporated herein by reference into the present application in its entirety.
FIELD OF THE INVENTIONThe present invention generally relates to intravascular medical devices and methods for monitoring and measuring fluid pressure. More specifically, the present invention relates to intravascular diagnostic devices and methods for monitoring and measuring fluid pressure at selected points in coronary vessels or arteries. Still more specifically, the present invention relates to intravascular devices and methods for monitoring and measuring fluid pressure at selected points in an artery on opposite sides of an occlusion or partial blockage. Those skilled in the art will recognize the benefits of applying the present invention to similar fields not discussed herein.
BACKGROUND OF THE INVENTIONAngioplasty procedures have gained wide acceptance in recent years as efficient and effective methods for treating many types of vascular disease. In particular, angioplasty is widely used for opening stenosis or occlusions in the coronary arteries, although it is also used for the treatment of stenosis in other parts of the vascular system.
The most widely used form of angioplasty makes use of a dilation catheter which has an inflatable balloon at its distal end. Inflation of the balloon at the site of the occlusion causes a widening of the vessel or artery to reestablish an acceptable blood flow through the vessel or artery.
It often is desirable to determine the severity of the occlusion in order to properly choose a dilation catheter or to make a determination as to whether treatment is required. Various techniques have been used to determine the severity of the occlusion. One way of determining the severity of the occlusion is to measure pressure both proximal to and distal of the occlusion.
Specifically, referring to
Devices that are used for this purpose include catheter-like members with some type of pressure-sensing device incorporated therein. One known device measures the pressure as a function of the deflection of a diaphragm located at the proximal end of the catheter. One problem associated with currently available pressure-sensing devices is that they are unable to measure pressure at points both proximal and distal to the occlusion without moving the device. When the device or catheter is moved, it can often cause physical changes to the occlusion thereby affecting the second pressure measurement. Further, unnecessary movement of the catheter can dislodge a portion of the plaque that forms the occlusion. Further, because it is often difficult to insert catheters in coronary arteries and other vessels, physicians are often reluctant to move a catheter in a proximal direction once the catheter is in position. Hence, once a physician inserts a catheter past the point of occlusion, the physician is often reluctant to move the catheter to a point proximal to the occlusion to take a pressure measurement if a catheter must be moved back to a location distal to the occlusion at a later time in the procedure.
Accordingly, there is a need for an improved intravascular pressure-sensing device which can monitor and measure pressure at multiple points along a vessel or artery without moving the device. Still further, there is a need for an intravascular pressure-sensing device which can monitor and measure pressure at multiple points along a vessel or artery simultaneously.
It would be desirable to make use of both multi-point intravascular pressure sensing devices and methods in order to provide a physician with sufficient diagnostic information to make a determination as to whether the occlusion should be treated. The ideal multiple point pressure measurement device would be accurate, low profile, flexible and have a fast response time. Both the cost and ease of use of the complete system needs to be considered as well to produce a commercially successful product. Presently available devices are not capable of simultaneously meeting these various requirements.
SUMMARY OF THE DISCLOSUREThe present invention overcomes the deficiencies of the prior art by providing a pressure monitoring and measuring device that comprises an elongated tube having an opening. The elongated tube is slidably received in a tubular sheath. The tubular sheath comprises at least two spaced apart openings. The elongated tube is slidably within the tubular sheath thereby allowing the opening of the elongated tube to be selectively aligned with both openings of the tubular sheath. In use, the elongated tube is positioned within the tubular sheath so that its opening is aligned with one of the openings of the tubular sheath. A pressure measurement is made in this position. Then, the elongated tube is moved within the tubular sheath so that its opening is aligned with the other opening of the tubular sheath. A second pressure measurement is made in this position.
In use, the above described embodiment would be introduced into a patient's vasculature in advance to a point whereby one of the openings of the tubular sheath is disposed distal to an occlusion and the other of the openings in the tubular sheath is disposed proximal to the occlusion. In this way, the elongated tube can be manipulated to take a pressure reading at points both distal and proximal to the occlusion without moving the tubular sheath.
In another embodiment, a method for monitoring and measuring pressure on opposing sides of an occlusion is disclosed. The method comprises the steps of providing a pressure measuring device comprising an elongated tube having an opening. The elongated tube is slidably received in a tubular sheath. The tubular sheath comprises either at least two spaced apart openings or one elongated opening. The elongated tube has a proximal end connected to a pressure transducer. The method further includes the step of inserting the pressure measuring device into a vessel having an occlusion until one of the openings of the tubular sheath is disposed on one side of the occlusion and the other openings of the tubular sheath is disposed on an opposite side of the occlusion. The method further includes the steps of aligning the opening of the elongated tube with one of the openings of the tubular sheath or a portion of the elongated opening on one side of the occlusion, measuring the pressure at the one opening of the tubular sheath through the elongated tube, aligning the opening of the elongated tube with the other openings of the tubular sheath or a portion of the elongated opening on an opposite side of the occlusion, and measuring the pressure at the other opening of the tubular sheath through the elongated tube.
Turning to
Still referring to
The device 14 further includes an elongated tube 21 that is slidably received within the tubular sheath 16. The elongated tube includes at least one opening 22. The elongated tube 21 can be moved with respect to the tubular sheath 16 so that the opening 22 of the elongated tube 21 can be moved from a position in substantial registry with the opening 18 of the tubular sheath 16 as shown in
The device 14 can be manufactured so that the elongated tube 21 is frictionally received within the tubular sheath 16. That is, the device 14 can be constructed so that the inside surface 23 of the tubular sheath 16 engages the outside surface 24 of the elongated tube 21 so that fluid communication between the two surfaces is substantially prevented. If the device 14 is constructed in this way, a closed end for the tubular sheath 16 is not necessary. As shown in
Returning to
Turning to
Further, referring to
Turning to
Both the sheath and tube of the disclosed pressure measuring devices can be made from a variety of materials, which will be apparent to those skilled in the art. The sheaths are preferably made from material suitable for the manufacture of pressure measuring guidewires. Such materials are commonly metallic, but it is anticipated that other polymeric materials may also be suitable for fabricating the sheath. The elongated tubes may also be made from metallic or polymer materials. Such suitable metallic or polymer materials include, but are not limited to polymer materials such as Pebax™, Arnitel™, polybutylene terephthalente (PBT), polyoxymethylene (POM), polyethylene (PE), polyethylene terephthalate (PET), polytetrafluoroethylene (PTFE), polyvinyl chloride (PVC), thermoplastic elastomer (TPE), polyamide and Nylon™ and metallic alloy materials such as Inconel 617™, Inconel 625™, Hastelloy S™, Hastelloy X™, Nimonic 90™, Incoloy 800™, MP35-N Elgiloy™, 304LV™, 316 LVM™, Aermet 100™, Aermet 310™, CRB-7™, Custom 450™, Custom 455™, Custom 465m™, NiMark 250™, NiMark 250 NCO™NiMark 300™, Nickel 200™, 304LV™316 LVM™, 321™, 347™, Aermet 100™, Aermet 310™, Haynes 214™, Haynes 230™, Inconel 600™, Inconel 601™, Inconel 617™, Inconel 625™, RA 333™, Hastelloy B™, Hastelloy N™, Hastelloy S™, Hastelloy W™, Hastelloy X™, Hastelloy C-276™, Haynes HR-120™, Haynes HR-160™, Nimonic 75™, Nimonic 86™, Haynes 556™, Incoloy 800™, Incoloy 800H™, Incoloy 800HT™, Incoloy 801™, Incoloy 802™, MP35-N™ and Elgiloy™ can be utilized.
While the specification describes preferred designs and methods, those skilled in the art will appreciate the spirit and scope of the invention with reference to the appended claims.
Claims
1. A pressure measuring medical device, comprising:
- a tubular sheath comprising at least one opening disposed in a distal end region thereof;
- a pressure transfer tube disposed within the tubular sheath, the pressure transfer tube comprising distal opening adjacent to a distal end region of the pressure transfer tube; and
- a pressure sensor coupled to the pressure transfer tube and positioned proximal to the distal opening;
- wherein the pressure transfer tube is capable of being disposed within a blood vessel so that the distal opening is positioned distally of an intravascular occlusion and the pressure sensor is positioned proximally of the intravascular occlusion.
2. The pressure measuring medical device of claim 1, wherein the device is configured to obtain a pressure measurement distal to the intravascular occlusion and a pressure measurement proximal to the intravascular occlusion simultaneously.
3. The pressure measuring medical device of claim 1, wherein the pressure transfer tube further comprises a proximal opening positioned proximally of the distal opening.
4. The pressure measuring medical device of claim 3, wherein the distal opening of the pressure transfer tube is in fluid communication with a first lumen of the of the pressure transfer tube and the proximal opening of the pressure transfer tube is in fluid communication with a second lumen of the pressure transfer tube.
5. The pressure measuring device of claim 4, wherein the first lumen is fluid isolated from the second lumen.
6. The pressure measuring device of claim 3, wherein the proximal opening is circumferentially offset from the distal opening.
7. The pressure measuring medical device of claim 1, further comprising a radiopaque marker disposed adjacent the distal opening of the pressure transfer tube.
8. The pressure measuring medical device of claim 1, further comprising a radiopaque marker disposed adjacent the distal end region of the tubular sheath.
9. A pressure measuring medical device, comprising:
- a pressure transfer tube, the pressure transfer tube comprising: a first opening and a second opening, the second opening axially spaced from the first opening; a first lumen in fluid communication with the first opening; and a second lumen in fluid communication with the second opening; and
- at least one pressure sensor coupled to the pressure transfer tube and positioned proximal to the first opening and the second opening.
10. The pressure measuring medical device of claim 9, wherein the pressure transfer tube is capable of being disposed within a blood vessel so that a the first opening is positioned distally of an intravascular occlusion and the second opening is positioned proximally of the intravascular occlusion.
11. The pressure measuring medical device of claim 10, wherein a pressure measurement at a location adjacent to the first opening and a pressure measurement at a location adjacent the second opening are obtained simultaneously.
12. The pressure measuring medical device of claim 9, wherein the first lumen is fluidly isolated from the second lumen.
13. The pressure measuring medical device of claim 9, wherein the second opening is circumferentially offset from the first opening.
14. The pressure measuring medical device of claim 9, further comprising at least one radiopaque marker disposed on the pressure transfer tube adjacent a distal end thereof.
15. A method for measuring pressure on opposing sides of an occlusion, the method comprising:
- inserting a pressure measuring device into a vessel having an occlusion, the pressure measuring device comprising: a pressure transfer tube disposed within the tubular sheath, the pressure transfer tube comprising a proximal opening and a distal opening axially spaced from one another; and at least one pressure sensor coupled to the pressure transfer tube and positioned proximal to the proximal opening;
- advancing the pressure measuring device through the vessel until the distal opening of the pressure transfer tube is on a first side of the occlusion and the proximal opening of the pressure transfer tube is on a second side of the occlusion;
- measuring the pressure through the distal opening; and
- measuring the pressure through the proximal opening.
16. The method of claim 15, wherein the measuring steps are carried out simultaneously
17. The method of claim 15, wherein the pressure transfer tube further comprises a first lumen in fluid communication with the distal opening and a second lumen in fluid communication with the proximal opening.
18. The method of claim 17, wherein the first lumen is fluidly isolated from the second lumen.
19. The method of claim 15, wherein the pressure transfer tube further comprises a radiopaque marker positioned adjacent to one of the proximal or distal openings.
20. The method of claim 15, wherein the distal opening in the pressure transfer tube is circumferentially offset from the proximal opening in the pressure transfer tube.
Type: Application
Filed: Aug 24, 2015
Publication Date: Dec 17, 2015
Applicant: BOSTON SCIENTIFIC SCIMED, INC. (MAPLE GROVE, MN)
Inventors: TIMOTHY G.J. EHR (ELK RIVER, MN), BRUCE H. ASMUS (MINNETONKA, MN)
Application Number: 14/834,399