Interventional catheter system and methods
An interventional catheter is adapted for treating a blood vessel. In an embodiment, the catheter includes an elongate shaft sized for insertion in a blood vessel and a stent positioned on a distal region of the elongate shaft. An expandable dilation member is coupled to a distal region of the elongate shaft. The expandable dilation member is adapted to expand outward. A stent containment member is positioned over the elongate shaft and the stent to contain the stent in a collapsed state.
1 . An interventional catheter system for treating a blood vessel, comprising:
an access sheath positionable transcervically in a carotid artery, the access sheath comprising a distal section attachable to a reverse flow path, a proximal extension outside of the reverse flow path and connected to the distal section by a connector;
an elongate stent delivery catheter sized for insertion through the access sheath when the access sheath is positioned in the carotid artery;
a stent positioned on a distal region of the stent delivery catheter;
a retractable stent containment member slidably positioned over the stent delivery catheter and the stent such that the stent containment member contains the stent in a collapsed state, wherein the retractable stent containment member is configured to be retracted from the stent delivery catheter by a length to expose the stent;
a control mechanism on a proximal region of the stent delivery catheter, the control mechanism being coupled to the stent containment member such that the control mechanism can be actuated to retract the stent containment member; and
wherein retraction of the stent containment member from the stent delivery catheter withdraws the stent containment member into the proximal extension at least partially proximal to the connector.
2 . A catheter system as in claim 1 , wherein the length is 25 cm.
3 . A catheter system as in claim 1 , wherein the stent containment member is completely retractable from the stent delivery catheter while the stent delivery catheter is positioned in the carotid artery.
4 . A catheter system as in claim 1 , wherein the stent containment member adds resistance to reverse flow through the reverse flow path in the access sheath and retraction of the stent containment member from the distal section of the access sheath into the proximal extension removes the resistance to the reverse flow through the reverse flow path and increases the level of reverse flow during stent expansion.
5 . A catheter system as in claim 1 , further comprising a flow shunt fluidly connectable to the access sheath and forming a part of the reverse flow path, wherein the flow shunt comprises two or more parallel flow paths and a valve to open or close one or more of the parallel flow paths selectively directing blood flow through the one or more of the parallel flow paths to adjust a state of flow through the flow shunt.
6 . A catheter system as in claim 1 , wherein the connector connects the reverse flow path to a flow shunt.
7 . A catheter system as in claim 5 , wherein one of the two or more parallel flow paths comprises a main lumen and a secondary lumen having a flow resistance that is higher than a flow resistance of the main lumen.
8 . A catheter system as in claim 7 , wherein the secondary lumen is longer and/or has a smaller diameter than the main lumen.
9 . A catheter system as in claim 8 , wherein a pressure drop is created in the main lumen across an inlet and outlet of the secondary lumen.
10 . A catheter system as in claim 7 , wherein the valve is configured to block flow through the main lumen and divert all flow to the secondary lumen increasing flow resistance and reducing rate of flow.
11 . A catheter system as in claim 10 , wherein the valve is configured to block flow through the secondary lumen and divert all flow to the main lumen decreasing flow resistance and increasing the rate of flow.
12 . A catheter system as in claim 1 , wherein the stent delivery catheter has a working length suitable for deployment through a transcervical access sheath into the common carotid artery.
13 . A catheter system as in claim 12 , wherein the working length is within the range of 40 cm to 60 cm.
14 . A catheter system as in claim 12 , wherein the working length is within the range of 40 cm to 75 cm.
15 . A catheter system as in claim 1 , wherein the stent is a self-expanding stent.