Expandable member for an electrophysiology catheter
Expandable electrophysiology catheters having electrodes mounted on splines of an expandable member are described. The splines of the expandable member include subsegments between a proximal location and a distal intersection at a central axis. The subsegments can include respective top-down profiles, and at least one of the top-down subsegment profiles is straight between the central axis and an adjacent top-down subsegment profile. The subsegments can be interconnected to extend continuously about the central axis from the proximal location to the distal intersection. Other embodiments are also described.
1. An expandable member, comprising:
a spline extending continuously between a pair of proximal locations on a catheter shaft and intersecting at a central axis, the spline including a first subsegment, a second subsegment, and a flex circuit, wherein the first subsegment, when viewed in an axial direction along the central axis, extends along a linear path in a radial direction between a distal intersection at the central axis and a distal subsegment end of the second subsegment, wherein the second subsegment has a uniform cross-sectional area and, when viewed in the axial direction along the central axis, undulates along a curvilinear path having a plurality of localized bends bending in different directions between the distal subsegment end and a proximal subsegment end of the second subsegment, and wherein the flex circuit includes a plurality of electrodes and the flex circuit is wrapped around a circumference of an outer surface of the spline.
2. The expandable member of claim 1 , wherein the second subsegment undulates about the central axis along the curvilinear path.
3. The expandable member of claim 2 , wherein the second subsegment undulates continuously.
4. The expandable member of claim 1 , wherein the spline includes a third subsegment, and wherein a third top-down profile of the third subsegment viewed in the axial direction along the central axis is straight between the proximal subsegment end of the second subsegment and the central axis.
5. The expandable member of claim 1 further comprising a reference electrode mounted on a non-tissue-contacting surface of the expandable member.
6. The expandable member of claim 1 , wherein the expandable member has a spherical envelope including one or more of a concave pole or a flattened pole.
7. The expandable member of claim 1 , wherein the distal intersection is axially aligned with the distal subsegment end.
8. The expandable member of claim 1 , wherein the distal intersection is proximal to the distal subsegment end.
9. The expandable member of claim 1 , wherein a first portion of the spline has a different radiopacity than a second portion of the spline.
10. An electrophysiology catheter, comprising:
a catheter shaft extending along a central axis between a proximal end and a distal end; and
an expandable member mounted on the distal end, the expandable member including a spline extending continuously between a pair of proximal locations on the catheter shaft and intersecting at the central axis, the spline including a first subsegment, a second subsegment, and a flex circuit, wherein the first subsegment, when viewed in an axial direction along the central axis, extends along a linear path in a radial direction between a distal intersection at the central axis and a distal subsegment end of the second subsegment, wherein the second subsegment has a uniform cross-sectional area and, when viewed in the axial direction along the central axis, undulates along a curvilinear path having a plurality of localized bends bending in different directions between the distal subsegment end and a proximal subsegment end of the second subsegment, and wherein the flex circuit includes a plurality of electrodes and the flex circuit is wrapped around a circumference of an outer surface of the spline.
11. The electrophysiology catheter of claim 10 , wherein the second subsegment undulates about the central axis along the curvilinear path.
12. The electrophysiology catheter of claim 10 , wherein the spline includes a third subsegment, wherein a third top-down profile of the third subsegment viewed in the axial direction along the central axis is straight between the proximal subsegment end of the second subsegment and the central axis.
13. The electrophysiology catheter of claim 10 further comprising a reference electrode mounted on a non-tissue-contacting surface of the expandable member.
14. The electrophysiology catheter of claim 10 , wherein a first portion of the spline has a different radiopacity than a second portion of the spline.
15. An electrophysiology catheter system, comprising:
a catheter shaft extending along a central axis between a proximal end and a distal end;
an expandable member mounted on the distal end, the expandable member including a spline extending continuously between a pair of proximal locations on the catheter shaft and intersecting at the central axis, the spline including a first subsegment, a second subsegment, and a flex circuit, wherein the first subsegment, when viewed in an axial direction along the central axis, extends along a linear path in a radial direction between a distal intersection at the central axis and a distal subsegment end of the second subsegment, wherein the second subsegment has a uniform cross-sectional area and, when viewed in the axial direction along the central axis, undulates along a curvilinear path having a plurality of localized bends bending in different directions between the distal subsegment end and a proximal subsegment end of the second subsegment, and wherein the flex circuit includes a plurality of electrodes and the flex circuit is wrapped around a circumference of an outer surface of the spline; and
a handle coupled to the proximal end of the catheter shaft.
16. The electrophysiology catheter system of claim 15 , wherein the second subsegment undulates about the central axis along the curvilinear path.
17. The electrophysiology catheter system of claim 15 , wherein the spline includes a third subsegment, wherein a third top-down profile of the third subsegment viewed in the axial direction along the central axis is straight between the proximal subsegment end of the second subsegment and the central axis.
18. The electrophysiology catheter system of claim 15 further comprising a reference electrode mounted on a non-tissue-contacting surface of the expandable member.
19. The electrophysiology catheter system of claim 15 , wherein a first portion of the spline has a different radiopacity than a second portion of the spline.
20. The electrophysiology catheter system of claim 15 further comprising:
an electrode on the spline; and
a reference electrode on the catheter shaft.