Intravascular blood pumps and pumps with expandable scaffolds
Catheter blood pumps that include an expandable pump portion. The pump portions include a collapsible blood conduit that defines a blood lumen. The collapsible blood conduits include a collapsible scaffold adapted to provide radial support to the blood conduit. The pump portion also includes one or more impellers. The collapsible scaffold may include portions of differing radial stiffness based on location of the one or more impellers therein.
1 . An intravascular blood pump, comprising:
a collapsible blood conduit defining an inner lumen for moving blood therethrough, the collapsible blood conduit including:
a proximal section defined by at least two annular rows of connector elements arranged around a central axis of the collapsible blood conduit;
a distal section defined by at least one annular row of connector elements arranged around the central axis of the collapsible blood conduit;
a central section disposed axially between the distal and proximal sections, the central section including a plurality of axially extending elongate elements arranged in a helical pattern, wherein the central section includes at least one of material or structure such that when a rotational force is applied to a distal end of the blood conduit, the central section is less resistant to collapse than the proximal and distal sections; and
a proximal impeller disposed within at least a portion of the proximal section.
2 . The intravascular blood pump of claim 1 , wherein the proximal, central and distal sections are coupled together.
3 . The intravascular blood pump of claim 1 , wherein the central section has a relative flexibility compared to the distal and proximal sections such that, in response to a lateral force on the blood conduit in the distal impeller section, the blood conduit deforms and assumes a configuration in which the central section has a higher degree of bend than the proximal and distal sections.
4 . The intravascular blood pump of claim 1 , wherein at least portions of the proximal and distal sections are free of helical scaffold patterns.
5 . The intravascular blood pump of claim 1 , wherein the axially extending elongate elements extend between the least two annular rows of connector elements in the proximal section.
6 . The intravascular blood pump of claim 1 , wherein the distal section is defined by at least two annular rows of connector elements arranged around the central axis of the collapsible blood conduit.
7 . The intravascular blood pump of claim 6 , wherein the axially extending elongate elements extend between the least two annular rows of connector elements in the distal section.
8 . The intravascular blood pump of claim 1 , wherein the proximal section is defined by at least four annular rows of connector elements arranged around the central axis of the collapsible blood conduit.
9 . The intravascular blood pump of claim 1 , wherein the connector elements in each annular row are in a zig-zag pattern.
10 . The intravascular blood pump of claim 1 , wherein an angle between the connector elements and the axially extending elongate elements ranges from about 10 degrees and 50 degrees.
11 . The intravascular blood pump of claim 1 , wherein an angle between the connector elements and the axially extending elongate elements ranges from about 10 degrees and 30 degrees.
12 . The intravascular blood pump of claim 1 , wherein an angle between the connector elements and the axially extending elongate elements ranges from about 30 degrees and 50 degrees.
13 . The intravascular blood pump of claim 1 , wherein an axial length of the blood conduit ranges from about 50 mm to about 80 mm.
14 . The intravascular blood pump of claim 1 , wherein the proximal section has a greater lateral bending stiffness than the distal section.
15 . The intravascular blood pump of claim 1 , wherein the collapsible blood conduit comprises a scaffold configured to transition between a collapsed state and an expanded state, wherein the scaffold has a diameter ranging from 5.0 mm to 10 mm in the expanded state and a diameter ranging from 2.5 mm to 4.5 mm in the collapsed state.
16 . The intravascular blood pump of claim 1 , further comprising a plurality of proximal struts extending proximally from the proximal section.
17 . The intravascular blood pump of claim 16 , further comprising a plurality of distal struts extending distally from the distal section.
18 . The intravascular blood pump of claim 17 , wherein the plurality of proximal struts numbers twice as many as the plurality of distal struts.
19 . The intravascular blood pump of claim 17 , wherein the intravascular blood pump includes ten proximal struts and five distal struts.
20 . The intravascular blood pump of claim 17 , wherein a width of the distal struts is greater than a width of the proximal struts.
21 . The intravascular blood pump of claim 20 , wherein the axially extending elongate elements increase in width near the distal section.
22 . An intravascular blood pump, comprising:
a collapsible blood conduit defining an inner lumen for moving blood therethrough, the collapsible blood conduit including:
a proximal section defined by at least two annular rows of connector elements arranged around a central axis of the collapsible blood conduit;
a plurality of proximal struts extending proximally from the proximal section;
a distal section defined by at least one annular row of connector elements arranged around the central axis of the collapsible blood conduit;
a plurality of distal struts extending distally from the distal section, wherein a width of the distal struts is greater than a width of the proximal struts;
a central section disposed axially between the distal and proximal sections, the central section including a plurality of axially extending elongate elements arranged in a helical pattern; and
a proximal impeller disposed within at least a portion of the proximal section.