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EP-4736932-A2 - SHEATH FOR SEALED ACCESS TO A VESSEL

EP4736932A2EP 4736932 A2EP4736932 A2EP 4736932A2EP-4736932-A2

Abstract

A sheath (10) for producing a fully sealed access to the interior of a vessel of an animal or human body comprises a base sheath (20) having a tubular body defining a pass-through channel (22). The base sheath (20) is adapted to be inserted into the vessel through a vessel aperture. The sheath further comprises an expansion device (26) which is adapted to cooperate with the base sheath (20) such that the outer diameter (d; D) of the sheath (10) increases in the region of the vessel aperture with the sheath (10) in a stationary position in the vessel and upon actuation of the expansion device (26).

Inventors

  • SIESS, THORSTEN
  • NIX, CHRISTOPH
  • KIRCHHOFF, FRANK
  • O'Carrol, Ger

Assignees

  • Abiomed Europe GmbH

Dates

Publication Date
20260506
Application Date
20140704

Claims (15)

  1. A sheath (10) for producing a fully sealed access to the interior of a vessel of an animal or human body, comprising a base sheath (20) having a tubular body defining a pass-through channel (22), with the base sheath (20) being adapted to be inserted into the vessel through a vessel aperture, characterized by an expansion device (26) which is adapted to cooperate with the base sheath (20) such that the outer diameter (d; D) of the sheath (10) increases in the region of the vessel aperture with the sheath (10) in a stationary position in the vessel and upon actuation of the expansion device (26).
  2. The sheath (10) according to claim 1, wherein the expansion device (26) is configured as an expansion sheath (26) that is displaceable on the base sheath (20) in the direction (R) of the vessel aperture.
  3. The sheath (10) according to claim 1, wherein the expansion device (26') is configured as an inflation tube that is spirally wound around the base sheath (20).
  4. The sheath (10) according to claim 1, wherein the expansion device (26a, 26b, 26c, 26d) includes a flexible portion (26a) of the base sheath between the proximal end (20b) and the distal end (20a), which flexible portion is configured to expand so as to increase the outer diameter of the sheath when the distal end portion of the base sheath is pulled in direction of the proximal end by means of a pulling means (26b, 26c, 26d).
  5. The sheath (10) according to claim 1, wherein the expansion device (26") includes a stretchable portion (26") of the base sheath between the proximal end (20b) and the distal end (20a), which stretchable portion is configured to attain a first thickness in a stretched condition and a second thickness, which is larger than the first thickness, in an unstretched condition, so as to increase the outer diameter of the sheath when the proximal end portion of the base sheath is released in direction of the vessel aperture from the stretched condition to the unstretched condition.
  6. The sheath (10) according to any of claims 1 to 5, comprising a sleeve (28) which encases the base sheath (20) and the expansion device (26, 26', 26a) such that the sleeve (28) is in contact with the vessel aperture in the stationary position of the sheath (10) in the vessel.
  7. The sheath (10) according to claim 2, comprising a sleeve (28) which encases the base sheath (20) and the expansion sheath (26) such that the sleeve (28) is in contact with the vessel aperture in the stationary position of the sheath (10) in the vessel, and that the expansion sheath (26) is displaceable on the base sheath (20) between the base sheath (20) and the sleeve (28).
  8. The sheath (10) according to any of claims 1 to 7, wherein the expansion device (26) is adapted to increase the outer diameter (d) of the sheath (10) in the region of the vessel aperture by 0.33 mm to 1.00 mm, preferably 0.33 mm to 1.33 mm, particularly preferably 0.33 mm to 1.66 mm.
  9. The sheath (10) according to any of claims 1 to 8, wherein a wall (25) of the tubular body of the base sheath (20) has a through channel (27) extending in the wall (25) from the distal end (20a) toward the proximal end (20b).
  10. The sheath (10) according to claim 9, wherein the channel (27) is adapted to conduct blood from the vessel to the proximal end (20b) of the sheath (10), wherein preferably the sheath (10) comprises a blood pressure measuring device (30) which is connected to the channel (27).
  11. The sheath (10) according to claim 10, comprising a temperature measuring element inserted through the channel (27).
  12. The sheath (10) according to any of claims 9 to 11, comprising a guidewire (50) which is introducible into the vessel from the proximal end (20b) of the sheath through the channel (27).
  13. The sheath (10) according to any of claims 1 to 12, comprising a fixation element (60) for fixing the sheath (10) to a patient, with the fixation element (60) having an area (62) spanning the base sheath (20) for applying a sterile cover, with the area (62) sloping down in a ramp shape on both sides of the base sheath (20) transversely to the principal direction of the base sheath, wherein preferably the fixation element (60) comprises a stop (64) for applying the sterile cover, said stop extending at the proximal end of the area (62) transversely to the principal direction of the base sheath.
  14. The sheath (10) according to any of claims 1 to 13, comprising a heart pump (70) having a supply catheter (40), with the sheath (10) being adapted to be arranged displaceably on the supply catheter (40).
  15. A method for producing a fully sealed access to the interior of a vessel of an animal or human body by means of a sheath (10) according to any of claims 1 to 14, comprising the steps of: - inserting the sheath (10) into a vessel aperture of the vessel; - increasing the outer diameter (d; D) of the sheath (10) in the region of the vessel aperture by actuating the expansion device (26) of the sheath (10), wherein preferably the method comprises the further step of determining a pressure that is applied to the aperture in order to determine a sufficient increase of the outer diameter (d; D) of the sheath (10).

Description

The present invention relates to a sheath for producing a fully sealed access to the interior of a vessel of an animal or human body, for example an artery. Sheaths are employed in different forms during percutaneous interventions on the human body, for example when introducing a heart catheter via an artery or vein, for example the femoral artery. Different steps of such an intervention will be set forth hereinafter in a brief and simplified form to lead up to the object of the invention. In a first phase, the vessel is punctured for this purpose with a puncture needle. Through this needle a first guidewire is then inserted into the vessel. The needle is removed and a first sheath is inserted into the vessel along the guidewire. The above steps are carried out according to the well-known "Seldinger technique". This sheath normally comprises a base sheath, a removable dilator and a hemostatic valve at the proximal end of the sheath, i.e. at the end of the sheath facing the practitioner's body. In connection with the present invention the anatomical direction terms will be chosen with reference to the practitioner. The sheath possesses an outer diameter of about 2 mm. The dilator and the guidewire are successively removed, so that only the base sheath of the first sheath remains partially in the vessel. In a second phase, a stiff guidewire is now inserted into the vessel through the remaining base sheath, for example up to a depth of 40 cm. Thereafter the base sheath is removed. The guidewire remains partially in the vessel. Optionally this can be followed by a further pre-dilation, which shall not be described here. Optionally or alternatively, instead of applying a small intermediary sheath, the puncture into the vessel can be up-dilated by applying various sizes of dilators over the originally deployed guidewire. Along the guidewire remaining in the vessel, that sheath is now inserted into the vessel through which the heart pump is to be introduced. In the context of the present application, an "introducer" or an "introducing sheath" is a sheath having a hemostatic valve. This introducing sheath normally possesses an inner diameter of from about 4.5 to 5 mm and an outer diameter of from about 5 to 6 mm. The basic structure of the introducing sheath is identical to the structure of the above-mentioned first sheath, i.e. it consists of an outer base sheath, a dilator and a hemostatic valve. Dilator and guidewire are removed again, with the base sheath of the introducing sheath remaining in the blood vessel. The access for the heart pump has now been created. Through the base sheath a guide catheter is now normally placed along the artery into the left ventricle. For this purpose there can be employed for example a so-called pigtail catheter, which consists of a thin tube and a soft distal precuved guiding tip. A supporting guidewire may already be inserted into the guide catheter extending therein, which supports the catheter. Said soft, supporting wire is thereafter removed, and a harder guidewire is inserted into the heart through the catheter. Along the hard guidewire the heart pump is inserted into the heart, after removal of the pigtail catheter. The inlet of the heart pump is then located in the left ventricle, the outlet in the aorta and the guidewire is retrieved. The pump is connected to a supply catheter which extends along the artery employed for placing the pump and which exits at the vessel aperture (puncture side). Alternatively, the pump can directly be inserted into the base sheath and can be delivered into the heart without the need for additional guide catheters and guidewires in case the pump has been designed with the appropriate features necessary to retrogradely pass the aortic valve in a trauma free manner. The introducing sheath that has been employed for inserting the heart pump is now removed from the vessel and pulled out completely before final removal is performed, for example by splitting along a predetermined separating line ("peel-away" technique). To now close the vessel at the vessel aperture again, i.e. to close the gap between the circumference of the hole in the vessel and the outer diameter of the supply catheter of the pump, a further sheath is inserted into the vessel along that portion of the heart-pump supply catheter that is located outside the body. The last-mentioned sheath is the subject matter of the present invention. Because it is also possible to displace or reposition the heart pump through this sheath, for example via the supply catheter, the sheath is also called a repositioning sheath (or "repo sheath"). To avoid a blood flow disturbance in the artery and potential low flow or foreign surface related thrombosis, the sheath should only be inserted into the vessel as deep as necessary and have an outer diameter just sufficient to close the vessel in a fully sealed manner, i.e. to stop bleeding or oozing that would otherwise occur. Normally the vessel apert