Anatomic fit of a percutaneous VAD for right heart support
An apparatus is disclosed including: a cannula having a shape closely matched to the anatomy of the right ventricle of the human heart, where the cannula has an outflow port configured to be located proximal the pulmonary artery and an inflow port located proximal the inferior vena cava. In some embodiments, the cannula is a close fit to the anatomy of at least 90%, 95%, or more of the population.
1. An apparatus comprising:
a cannula comprising a shape memory material configured to provide the cannula with a shape closely matched to the anatomy of the right ventricle of the human heart, wherein the cannula has:
an outflow port configured to be located proximal the pulmonary artery (PA);
an inflow port configured to be located proximal the inferior vena cava (IVC);
a primary section corresponding to the path from a diaphragm fibrous ring in the IVC to the IVC to right atrium (RA) transition (IVC-RA), extending in a first direction;
a secondary section corresponding to the path from the IVC-RA to the tricuspid valve (TV), extending in a second direction different to the first direction;
a tertiary section corresponding to the path from the TV to the pulmonary valve (PV), extending in a third direction different from the first and second directions; and
a quaternary section corresponding to the path between the PV and the left branch of the PA, extending in a fourth direction, different from the first, second and third directions,
wherein:
the primary section extends from a point A to a point B and includes the inflow port proximal point A;
the secondary section extends from said point B to a point C;
the tertiary section extends from said point C to a point D; and
the quaternary section extends from said point D to a point E, having the outflow port proximal said point E;
wherein:
the primary, secondary and tertiary sections lie substantially in a first plane containing said points A, B, and C; and
the quaternary section lies substantially in a second plane containing points C, D, and E, the second plane being oriented to the first plane at an angle of about 30 degrees.
2. The apparatus of claim 1 , wherein the primary section extends to the inflow port and the inflow port is configured to be located in the IVC, beyond the diaphragm fibrous ring of the IVC.
3. The apparatus of claim 1 , wherein:
the primary section has a length of about 28 mm;
the secondary section has a length of about 44 mm;
the tertiary section has a length of about 48 mm;
the quaternary section has a length of about 56 mm;
the secondary section is oriented to the first segment at an angle of about 63 degrees in the first plane, with a bend radius of curvature of about 25 mm;
the tertiary section is oriented to the first segment at an angle of about −30 degrees in the first plane, with a bend radius of curvature of about 45 mm;
the quaternary section is oriented to the third segment at an angle of about −87 degrees in the second plane, with a bend radius of curvature of about 25 mm.
4. The apparatus of claim 1 , wherein the cannula is formed of a biocompatible material.
5. The apparatus of claim 4 , further comprising an extension extending from the end of the quaternary section at a point proximal point E, the extension lying substantially in a third plane oriented at an angle of about −30 degrees to the second plane.
6. The apparatus of claim 1 , wherein the cannula is formed of a substantially rigid material.
7. The apparatus of claim 1 , wherein the cannula is formed of an at least partially flexible substantially rigid material.
8. The apparatus of claim 1 , wherein the cannula comprises a polyurethane tube reinforced with a surrounding coil of nitinol.
9. The apparatus of claim 1 , comprising a percutaneous ventricular assist device comprising the cannula, and comprising at least one pump located within the cannula.
10. The apparatus of claim 1 , wherein the cannula has a shape closely matched to the anatomy of at least 80%, at least 85%, at least 90% or at least 95% of the adult human population.
11. A method comprising:
forming a cannula as recited in claim 1 .
12. A method comprising:
implanting the apparatus of claim 1 in a human heart.
13. The apparatus of claim 1 , wherein the cannula further comprises an extension that extends the cannula non-hydraulically beyond the outflow port.
14. The apparatus of claim 13 , wherein the extension is flexible.
15. The apparatus of claim 13 , wherein the extension comprises a pigtail tip.
16. The apparatus of claim 1 , wherein the cannula is configured for percutaneous delivery.
17. A method comprising:
receiving medical image data corresponding the anatomy of the right ventricle of each of a plurality of human subjects;
processing the medical image data to determine landmark information indicative of the position of a plurality of anatomical landmarks, said landmarks including an inferior vena cava (IVC), right atrium (RA), tricuspid valve (TV), pulmonary valve (PV) and pulmonary artery (PA);
generating a cannula design based on the landmark information; and
fabricating a cannula comprising a shape memory material configured to provide the cannula with a shape based on the cannula design,
wherein the cannula design includes:
an outflow port configured to be located proximal the PA;
an inflow port configured to be located proximal the IVC;
a primary section corresponding to the path from a diaphragm fibrous ring in the IVC to the IVC to RA transition (IVC-RA), extending in a first direction;
a secondary section corresponding to the path from the IVC-RA to the TV, extending in a second direction different to the first direction;
a tertiary section corresponding to the path from the TV to the PV, extending in a third direction different from the first and second directions; and
a quaternary section corresponding to the path between the PV and the left branch of the PA, extending in a fourth direction, different from the first, second and third directions,
wherein:
the primary section extends from a point A to a point B and includes the inflow port proximal point A;
the secondary section extends from said point B to a point C;
the tertiary section extends from said point C to a point D; and
the quaternary section extends from said point D to a point E, having the outflow port proximal said point E;
wherein:
the primary, secondary and tertiary sections lie substantially in a first plane containing said points A, B, and C; and
the quaternary section lies substantially in a second plane containing points C, D, and E, the second plane being oriented to the first plane at an angle of about 30 degrees.
18. The method of claim 17 , wherein the information indicative of the position of the IVC, RA, TV, PV and PA comprises:
a length and an angle between the IVC and the RA;
a length and an angle between the RA and the TV;
a length and an angle between the TV and PV; and
a length and an angle between the PV and PA.
19. The method of claim 17 , wherein the cannula has a shape closely matched to the anatomy of at least 80%, at least 85%, at least 90% or at least 95% of the adult human population.
20. A product comprising:
a cannula fabricated using the method of claim 17 ; and
a pump configurable to pump blood entering the inflow port.
21. The product of claim 20 , wherein the pump is enclosed within the cannula.
22. The method of claim 17 , wherein the cannula design includes an extension that extends the cannula non-hydraulically beyond the outflow port.
23. The method of claim 17 , wherein the cannula is configured for percutaneous delivery.