Abstract: A stent (1) comprising a tubular frame (2) comprising a first end (3) and a second end and a longitudinal axis (4) therebetween. The frame (2) comprises a plurality of struts (9) defining a generally cylindrical portion comprising a longitudinally extending helical fin (11) protruding radially inwardly and having a helix angle. The angle, relative to the longitudinal axis (4), of at least some of the struts (9) in the helical fin (11) is substantially aligned with the helix angle of the helical fin (11).

Abstract: A conduit arrangement (1) comprises distal and proximal ends (2,3) and two tubular lumens (10,11). Each tubular lumen (10,11) comprises a longitudinal axis extending between the distal and proximal ends (2,3) and independently permits fluid communication between the distal and proximal ends (2,3). The interior of each of the two tubular lumens is made from a biocompatible material. At least a portion of at least one tubular lumen (10, 11) is capable of imparting helical flow on fluid passing through said portion of the tubular lumen (10,11). The helical flow is spiral laminar flow.

Abstract: An artificial or modified natural blood flow tubing has a helical-flow inducer to induce helical flow in such a fashion as to eliminate or reduce turbulence. One inducer is a tubular stent of expansible mesh having a helical vane.

Abstract: A stent (1) comprising a tubular frame (2) comprising a first end (3) and a second end and a longitudinal axis (4) therebetween. The frame (2) comprises a plurality of struts (9) defining a generally cylindrical portion comprising a longitudinally extending helical fin (11) protruding radially inwardly and having a helix angle. The angle, relative to the longitudinal axis (4), of at least some of the struts (9) in the helical fin (11) is substantially aligned with the helix angle of the helical fin (11).

Abstract: A conduit arrangement (1) comprises distal and proximal ends (2,3) and two tubular lumens (10,11). Each tubular lumen (10,11) comprises a longitudinal axis extending between the distal and proximal ends (2,3) and independently permits fluid communication between the distal and proximal ends (2,3). The interior of each of the two tubular lumens is made from a biocompatible material. At least a portion of at least one tubular lumen (10, 11) is capable of imparting helical flow on fluid passing through said portion of the tubular lumen (10,11). The helical flow is spiral laminar flow.

Abstract: A tubular graft comprising an internal helical formation which imparts helical flow on fluid passing through the tubular graft. One end of the tubular graft is tapered from an inner base to an outer tip.

Abstract: An artificial or modified natural blood flow tubing has a helical-flow inducer to induce helical flow in such a fashion as to eliminate or reduce turbulence. One inducer is a tubular stent of expansible mesh having a helical vane.

Abstract: A tubular conduit comprising: a tubular portion made from a flexible material. There is an external helical formation extending around the exterior of, and parallel to the axis of, the tubular portion and defining a first region of the tubular portion. The external helical formation is for supporting the tubular portion. There is also an internal helical formation, protruding inwardly of the interior of the tubular portion and extending parallel to the axis of the tubular portion and defining a second region of the tubular portion. The internal helical formation is for imparting helical flow on fluid passing through the tubular portion. The first region does not extend throughout the second region.

Abstract: A tubular conduit is disclosed. The tubular conduit comprises a tubular portion made from a flexible material and an axially extending external helical formation located around the outside of the tubular portion. The external helical formation is for supporting the tubular portion. Optionally the tubular portion also comprises an axially extending internal helical protrusion, which imparts a helical flow to a fluid passing through the tubular portion. It is preferred that the tubular conduit is a vascular graft.

Abstract: A vascular access graft (1) comprises an elongate conduit (2) having proximal and distal ends (3, 4). At least a portion of the elongate conduit (2) has a self-sealing property such that the portion remains impermeable after puncturing by a dialysis needle. The vascular access graft (1) also comprises a helical fin (6) projecting inwardly from the inner surface (5) of the elongate conduit (2) and extending parallel to the axis of the elongate conduit (2).

Abstract: A tubular conduit is disclosed. The tubular conduit comprises a tubular portion made from a flexible material and an axially extending external helical formation located around the outside of the tubular portion. The external helical formation is for supporting the tubular portion. Optionally the tubular portion also comprises an axially extending internal helical protrusion, which imparts a helical flow to a fluid passing through the tubular portion. It is preferred that the tubular conduit is a vascular graft.

Abstract: A tubular graft comprising an internal helical formation which imparts helical flow on fluid passing through the tubular graft. One end of the tubular graft is tapered from an inner base to an outer tip.

Abstract: A tubular graft comprising an internal helical formation which imparts helical flow on fluid passing through the tubular graft. One end of the tubular graft is tapered from an inner base to an outer tip.

Abstract: A tubular conduit is disclosed. The tubular conduit comprises a tubular portion made from a flexible material and an axially extending external helical formation located around the outside of the tubular portion. The external helical formation is for supporting the tubular portion. Optionally the tubular portion also comprises an axially extending internal helical protrusion, which imparts a helical flow to a fluid passing through the tubular portion. It is preferred that the tubular conduit is a vascular graft.

Abstract: A tubular conduit is disclosed. The tubular conduit comprises a tubular portion made from a flexible material and an axially extending external helical formation located around the outside of the tubular portion. The external helical formation is for supporting the tubular portion. Optionally the tubular portion also comprises an axially extending internal helical protrusion, which imparts a helical flow to a fluid passing through the tubular portion. It is preferred that the tubular conduit is a vascular graft.