Edwards Lifesciences Corporation

Alpana Kiran Gowdar

Thanh Huy Le

Tung Thanh Le

Sonny Tran

Richard D White

Pu Zhou

Michael G Valdez

Erik E Bulman

Yidong M Zhu

Baigui Bian

Timothy A Geiser

Yong Gao

David D Williams

Sovanpheap Mak

Disclosed herein are expandable introducer sheaths and methods of making and using the same. The sheaths minimize trauma to a patient's vasculature by allowing for temporary expansion of a portion of the sheath to accommodate passage of a delivery system for an implant, then return to a non-expanded state after the passage of the device. The sheath includes a foldable inner member having a detached flap structure at its distal tip that facilitates expansion of the sheath lumen to increased diameters, and an elastomeric distal end that reduces push and retrieval forces therethrough. The sheath can include a hemostasis seal on its proximal end to prevent the leakage of blood out of the sheath and prevent ballooning of outer layer of the sheath.

Expandable sheath and methods of using the same

A delivery sheath includes an outer tubular layer and an initially folded inner tubular layer. When an implant passes therethrough, the outer tubular layer expands and the inner tubular layer unfolds into an expanded lumen diameter. The sheath may also include selectively placed longitudinal support rods that mediate friction between the inner and outer tubular layers to facilitate easy expansion, thereby reducing the push force needed to advance the implant through the sheath's lumen.

Expandable sheath

A delivery sheath includes an elastic outer tubular layer and an inner tubular layer having a thick wall portion integrally connected to a thin wall portion. The inner tubular layer can have a compressed or folded condition wherein the thin wall portion folds onto an outer surface of the thick wall portion under urging of the elastic outer tubular layer. When an implant passes therethrough, the outer tubular layer stretches and the inner tubular layer unfolds into an expanded lumen diameter. Once the implant passes, the outer tubular layer again urges the inner tubular layer into the compressed condition with the sheath reassuming its smaller profile. The sheath may also include selectively placed longitudinal rods that mediate friction between the inner and outer tubular layers to facilitate easy expansion and collapse, thereby reducing the push force needed to advance the implant through the sheath's lumen.

An expandable introducer sheath for passage of implant delivery catheters, such as catheters for delivery of prosthetic heart valves. The expandable sheath balances the amounts, shapes and positions of various stiff and elastic structures in the sheath to selectively program the expandability and buckling stiffness of the sheath. The expandable sheath can include, for example, an expandable tubular layer that includes alternating stiff and elastic wall portions of a single radial thickness. The combination of stiff and elastic wall portions allow for torque and push strength to advance the expandable sheath while at the same time accommodating temporary expansion. The expandable sheath can also be reinforced with a tubular layer of braided fibers or a stent structure for additional strength. Other embodiments include selective use of slots or gaps at the distal end of a stiff wall portion to enhance expandability and distribute strain.

Expandable sheath with elastomeric cross sectional portions

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Newport Beach, CA, United States of America

Alpana Kiran Gowdar