Perfusion balloon design
Disclosed herein are designs for improved inflatable structures for use during minimally invasive cardiovascular procedures. These inflatable structures facilitate the perfusion of blood through an anatomical structure, such as a heart valve, during the cardiovascular procedure. The inflatable structures are formed of a plurality of balloons arranged radially around a central location. The plurality of balloons form a lumen through which blood flows. Each balloon of the plurality is shaped or configured to stabilize the adjacent balloons, limiting their movement relative to each other. For example, some embodiments can feature balloons with a keystone shape that limits movement of the balloons inward toward the lumen. Some implementations can also include a support coil running through the lumen. The support coil holds enables the lumen to be open to perfusion even in the early stages of balloon inflation.
1. A balloon catheter for insertion into a body lumen with blood flowing therethrough, the balloon catheter comprising:
an elongate member defining an inflation lumen, the elongate member having a proximal end and a distal end, a plurality of balloons coupled to the distal end of the elongate member and connected in fluid communication with the inflation lumen of the elongate member, and a plurality of interlocking mechanisms, wherein one interlocking mechanism is positioned between each adjacent pair of the balloons,
wherein the balloons are arranged circumferentially about a central axis so as to form an additional lumen extending along the central axis and wherein the lumen is configured to allow passage of the blood therethrough, wherein each of the balloons comprises a non-circular cross-sectional shape having at least two substantially straight side portions extending radially relative to the central axis, and wherein each substantially straight side portion at least partially abuts the substantially straight side portion of an adjacent one of the balloons.
2. The balloon catheter of claim 1 , further comprising a support coil coupled to the distal end of the elongate member, the support coil extending along the central axis within the additional lumen and at least partially supporting the balloons.
3. The balloon catheter of claim 2 , wherein the support coil has a dumbbell shape with a tubular central region extending between opposing bulbous end regions.
4. The balloon catheter of claim 3 , wherein a pitch of the support coil at the bulbous end regions is greater than a pitch of the support coil at the tubular central region to facilitate passage of the blood therethrough each of the bulbous end regions.
5. The balloon catheter of claim 4 , further comprising a prosthetic heart valve crimped over the balloons and the tubular central region of the support coil.
6. The balloon catheter of claim 1 , wherein the each of the at least two substantially straight side portions converge toward each other extending toward the central axis.
7. The balloon catheter of claim 1 , wherein the non-circular cross-sectional shape of each of the balloons further comprises an inner portion extending between a radially inward end of each of the at least two substantially straight side portions and an outer portion extending between a radially outward end of each of the at least two substantially straight side portions.
8. The balloon catheter of claim 7 , wherein the inner portion defines a portion of the additional lumen.
9. The balloon catheter of claim 8 , wherein the outer portion is longer than the inner portion and wherein the cross-sectional shape is a keystone shape.
10. The balloon catheter of claim 1 , wherein ends of the balloons have openings defined therebetween, the openings establishing fluid communication between the additional lumen and the blood in the body lumen.
11. The balloon catheter of claim 10 , wherein the ends of the balloons taper to small diameter tubes and are combined into a manifold in communication with the inflation lumen of the elongate member.
12. The balloon catheter of claim 1 , wherein each of the interlocking mechanisms includes a protrusion and a recess, the recess configured to receive the protrusion.
13. The balloon catheter of claim 12 , wherein the protrusion has a U-shape and the recess has a corresponding U-shape.
14. The balloon catheter of claim 1 , further comprising a surrogate valve configured to block openings defined between ends of the balloons to prevent backflow of blood.
15. The balloon catheter of claim 14 , wherein the surrogate valve includes a plurality of leaflets configured to extend over the openings during backflow of blood.
16. The balloon catheter of claim 15 , wherein the leaflets are further configured to deflect away from the openings during forward flow of blood.
17. The balloon catheter of claim 1 , wherein at least one of the balloons includes at least one web extending between and connected to the at least two substantially straight side portions.
18. A method of using a balloon catheter, the method comprising:
flowing fluid through an inflation lumen into a plurality of balloons coupled to a distal end of an elongate member;
wherein each of the balloons comprises a non-circular cross-sectional shape having at least two substantially straight side portions extending radially relative to a central axis, and wherein each substantially straight side portions at least partially abut the substantially straight side portion of an adjacent one of the balloons;
positioning the balloons in a circumferentially adjacent arrangement and inflating the balloons to form a perfusion lumen extending along the central axis about which the balloons are arranged;
maintaining stability of the balloons by abutting radially extending sides of the balloons against each other;
a plurality of interlocking mechanisms, wherein one interlocking mechanism is positioned between each adjacent pair of the balloons; and
perfusing a second fluid from one end of the circumferentially adjacent arrangement of balloons, through the perfusion lumen and to another end of the circumferentially adjacent arrangement of balloons.
19. The method of claim 18 , further comprising supporting the balloons on a helically wound coil extending through the perfusion lumen.