Expandable mechanical hemodynamic support systems, devices, and methods
Some embodiments of percutaneous ventricular assist devices have a two-part design that includes a housing component and a separately deployable rotatable inner catheter component. The housing component can include an expandable pump housing. The inner catheter can include an expandable pump impeller and an associated flexible drive shaft. The drive shaft can be coupled to a motor located external to the patient. The motor can rotate the drive shaft to spin the pump impeller inside of the pump housing, causing blood to be pumped within the patient. In some embodiments, the pump impeller is inflatable or self-expandable. The two-part percutaneous ventricular assist devices with inflatable or self-expandable pump impellers are designed to have very small delivery profiles. Accordingly, various deployment modalities, including radial artery deployment, are practicable using the two-part percutaneous ventricular assist devices described herein.
1. A percutaneous ventricular assist device comprising:
an elongate flexible drive shaft defining a lumen;
an inflatable balloon-based pump impeller attached to a distal end portion of the drive shaft, the pump impeller comprising:
a body with an outer surface, wherein the body is expandable in response to receiving an inflation fluid supplied via the lumen; and
one or more ridges attached to the body of the pump impeller and disposed around the outer surface of the body, wherein each ridge comprises a tube that defines its own separate internal tubular lumen extending along the ridge, and wherein each ridge is expandable in response to receiving the inflation fluid into its own separate internal tubular lumen; and
a pump housing,
wherein the percutaneous ventricular assist device is configured to pump blood when: (i) the pump impeller is positioned in the pump housing, (ii) the pump impeller is expanded, and (iii) the drive shaft is rotated.
2. The percutaneous ventricular assist device of claim 1 , wherein the one or more ridges are disposed around only a portion of the body.
3. The percutaneous ventricular assist device of claim 2 , wherein the portion of the body is a distal portion of the body.
4. The percutaneous ventricular assist device of claim 3 , wherein the body has a maximum diameter portion located between a proximal portion of the body and the distal portion of the body.
5. The percutaneous ventricular assist device of claim 4 , wherein the proximal portion of the body has a smooth outer surface.
6. The percutaneous ventricular assist device of claim 4 , wherein the body has a smaller outer diameter distally of the maximum diameter portion than proximally of the maximum diameter portion.
7. The percutaneous ventricular assist device of claim 1 , wherein the pump housing is reconfigurable between a low-profile delivery configuration and a radially expanded configuration, and wherein the pump housing defines one or more outlet openings.
8. The percutaneous ventricular assist device of claim 7 , wherein the pump housing defines one or more relief cutouts around a periphery of each of the one or more outlet openings.
9. The percutaneous ventricular assist device of claim 7 , wherein the one or more outlet openings comprise exit port flaps that operate as one-way valves to allow fluid flow out of the pump housing and prevent fluid flow into the housing through the one or more outlet openings.
10. The percutaneous ventricular assist device of claim 1 , further comprising an inlet cannula extending from the pump housing, and wherein the inlet cannula defines one or more inlet openings.
11. The percutaneous ventricular assist device of claim 10 , wherein the inlet cannula is reconfigurable between a low-profile delivery configuration and a radially expanded configuration.
12. The percutaneous ventricular assist device of claim 1 , wherein the body comprises a tapered body.
13. The percutaneous ventricular assist device of claim 1 , further comprising a drive shaft housing extending proximally from the pump housing and defining a housing lumen configured to slidably receive the drive shaft and the pump impeller when the pump impeller is deflated.
14. The percutaneous ventricular assist device of claim 1 , wherein the one or more ridges spiral around a central axis of the pump impeller.
15. The percutaneous ventricular assist device of claim 1 , wherein the pump impeller has no internal support structure.