EXPANDABLE TRANS-SEPTAL SHEATH

• US 20080243081A1
• Filed: 03/28/2008
• Published: 10/02/2008
• Est. Priority Date: 03/30/2007
• Status: Active Grant

• Current Assignee: Terumo Medical Corporation (Terumo Corporation)
• Original Assignee: Onset Medical Corp. (Terumo Corporation)
• Inventors: Nance, Edward J., Lenker, Jay, Nguyen, Hyun T.
• Granted Patent: US 8,900,214 B2
• Time in Patent Office: Days
• US Class Current: 604/164.03
• CPC Class Codes: A61B 17/3439 with means for changing the inner diameter of the cannula, e.g. expandable A61B17/3423, A61B17/3431 take precedence; catheters A61M25/0662
• CPC Class Codes: A61B 17/3478 Endoscopic needles, e.g. for infusion biopsy needles A61B10/0233; catheters with injection needles A61M25/0067
• CPC Class Codes: A61B 2017/00243 cardiac
• CPC Class Codes: A61B 2017/00247 Making holes in the wall of the heart, e.g. laser Myocardial revascularization
• CPC Class Codes: A61B 2017/00278 Transorgan operations, e.g. transgastric
• CPC Class Codes: A61B 2017/3425 for internal organs, e.g. heart ports
• CPC Class Codes: A61B 2018/00392 Transmyocardial revascularisation
• CPC Class Codes: A61F 2/2427 Devices for manipulating or deploying heart valves during implantation
• CPC Class Codes: A61M 2025/0024 Expandable catheters or sheaths
• CPC Class Codes: A61M 25/0662 Guide tubes

Abstract

Disclosed is an expandable transluminal sheath, for introduction into the body while in a first, low cross-sectional area configuration, and subsequent expansion of at least a part of the distal end of the sheath to a second, enlarged cross-sectional configuration. The sheath is configured for use in the vascular system and has utility in the performance of procedures in the left atrium. The access route is through the inferior vena cava to the right atrium, where a trans-septal puncture, followed by advancement of the catheter is completed. The distal end of the sheath is maintained in the first, low cross-sectional configuration during advancement to the right atrium and through the atrial septum into the left atrium. The distal end of the sheath is subsequently expanded using a radial dilatation device. In an exemplary application, the sheath is utilized to provide access for a diagnostic or therapeutic procedure such as electrophysiological mapping of the heart, radio-frequency ablation of left atrial tissue, placement of left atrial implants, mitral valve repair, or the like.

Claims

1. An expandable endovascular access sheath adapted for providing minimally invasive access to the left atrium, comprising:

an axially elongate sheath tube with a proximal end, a distal end, and a central through lumen;

a distal region of the sheath which is expandable in circumference in response to outward pressure applied therein,

a hub affixed to the proximal end of the sheath tube, the hub adapted to facilitate the passage of instrumentation;

a central obturator, which serves to occlude the central lumen of the sheath during insertion further comprising a hub that releasably locks to the hub of the sheath; and

a guidewire lumen within the obturator, capable of passing over standard medical guidewires and which will allow the obturator and sheath to track over said guidewires through tortuosity such as that found tracking into the right and left atria, and any transitions therebetween;

wherein the obturator is a balloon dilator capable of expanding the distal region of the sheath from a collapsed configuration to an expanded configuration.

2. The endovascular access sheath of claim 1 wherein the sheath tube comprises:

an outer layer, an inner layer, and a reinforcing layer wherein the outer layer and the inner layer are fabricated from polymeric materials.

3. The endovascular access sheath of claim 1 where the sheath tube

comprises a reinforcing layer embedded within a membrane layer fabricated from polymeric materials.

4. The endovascular access sheath of claim 2 wherein the reinforcing layer is a coil of metal.

5. The endovascular access sheath of claim 2 wherein the reinforcing layer is a braid.

6. The endovascular access sheath of claim 2 wherein the inner and outer layer are fabricated from different polymers.

7. The endovascular access sheath of claim 2 wherein the length of the sheath is between 50 and 250 cm.

8. The endovascular access sheath of claim 2 wherein the inner lumen of the sheath ranges between 6 and 30 French when the distal region is fully expanded.

23. The endovascular access sheath of claim 1, further comprising at least one guide tube disposed at least partially within the central lumen, the at least one guide tube having a proximal guide tube end, a distal guide tube end and a guide tube lumen extending therebetween.

24. The endovascular access sheath of claim 23, further comprising a removable obturator disposed within the guide tube lumen.

25. The endovascular access sheath of claim 23, wherein the at least one guide tube is configured to extend beyond the distal end of the sheath tube.

26. The endovascular access sheath of claim 25, wherein the at least one guide tube comprises a pre-curved distal guide tube portion proximate the distal guide tube end.

27. The endovascular access sheath of claim 1, further comprising a distal fairing affixed to the distal end of the sheath tube.

28. The endovascular access sheath of claim 27, wherein the distal fairing is affixed to the distal end of the sheath tube by a retainer.

9. A method of instrumenting the left atrium comprising the steps of:

routing a guidewire into the right atrium from a peripheral vein,

inserting a sheath with a pre-inserted dilator into the patient over the guidewire, and advancing the sheath to a treatment or diagnostic site within the right atrium of the heart, wherein the sheath comprises a distal region which is collapsed in diameter,

performing a trans-septal puncture between the right and left atrium and advancing the collapsed sheath through the puncture into the left atrium,

dilating the distal region of the sheath so that the distal region of the sheath is expanded, wherein a full-size lumen exists within the sheath and extending from the proximal end to the distal end,

collapsing the dilator by an action applied at the proximal end of said dilator,

removing the dilator from the sheath,

inserting instrumentation through the lumen of the sheath into the left atrium,

performing therapy or diagnosis with the instrumentation, and

removing the sheath from the patient.

10. The method of claim 9 wherein the dilation step is performed by inflating a balloon on the dilator.

11. The method of claim 9 wherein the dilation step is performed by attaching a liquid-filled inflation device to a balloon inflation port at the distal end of the dilator and infusing liquid under pressure into the dilator.

12. The method of claim 9 wherein the step of collapsing the dilator comprises withdrawing a plunger on the inflation device to withdraw liquid from the dilator.

13. The method of claim 9 wherein the therapy comprises electrophysiology energy delivery.

14. The method of claim 9 wherein instrumentation comprises inserting two or more catheters through the sheath to perform the therapy.

15. The method of claim 9 wherein the therapy comprises delivering an implant into the left atrium.

16. The method of claim 9 wherein dilation of the sheath also comprises the step of dilating anchors within the atria.

17. The method of claim 9 wherein the full-size lumen created in the expandable region by the dilator is substantially larger than the lumen of the proximal non-expandable tubing.

18. The method of claim 9 wherein the full-size lumen created in the expandable region by the dilator is substantially smaller than that of the proximal sheath lumen.

19. The method of claim 9 wherein the full-size lumen created in the expandable region by the dilator is substantially the same size as that of the proximal sheath lumen.

20. A sheath adapted for insertion into the right or left atrium of the heart comprising:

a means for tracking a sheath over an already placed guidewire to a target treatment site in the right or left atrium of the heart,

a means for articulating the distal end of the sheath, wherein the sheath is diametrically collapsed along at least a portion of its distal length,

a means for dilating at least a portion of the distal end of the sheath, wherein the dilating means is operable from the proximal end of the sheath, and

a means for removal of the sheath from the patient.

21. The sheath of claim 20 further comprising means for performing instrumentation, infusion of material into the atria of the heart, or withdrawal of material from the atria of the heart.

22. The sheath of claim 20 further comprising means for readily visualizing, positioning, and orienting said sheath using visualization techniques employing X-rays.