Method and apparatus for creation of drug delivery and/or stimulation pockets in myocardium

• US 6,482,220 B1
• Filed: 11/22/1999
• Issued: 11/19/2002
• Est. Priority Date: 12/26/1996
• Status: Expired due to Fees

• Current Assignee: Eclipse Surgical Technologies, Inc. (Cryolife Incorporated)
• Original Assignee: Eclipse Surgical Technologies, Inc. (Cryolife Incorporated)
• Inventors: Mueller, Richard L.
• Primary Examiner(s): Shay, David M.
• Application Number:
  US09/444,772
• Time in Patent Office: 1,093 Days
• Field of Search: 606/1, 606/7, 606/10-13, 606/167, 606/170, 606/174, 606/184, 606/185, 604/20, 604/22, 604/48
• US Class Current: 606/174
• CPC Class Codes: A61B 18/08 by means of electrically-heated probes
• CPC Class Codes: A61B 2017/00247 Making holes in the wall of the heart, e.g. laser Myocardial revascularization
• CPC Class Codes: A61B 2017/22082 after introduction of a substance
• CPC Class Codes: A61B 2018/00392 Transmyocardial revascularisation

Abstract

An apparatus and method for creating drug-filled pockets within muscle tissue, such as myocardium of the heart for increasing angiogenesis. More particularly, the apparatus has an excising assembly with a dilator tip for penetrating and advancing through the surface and body of a muscle or organ, such as the heart. Preferably, the dilator tip has a low level laser optical fiber emission to ease the passage of the excising assembly and provide thermal damage which also stimulates angiogenesis. More preferably, the dilator tip also disperses a pharmacologically active substance as the apparatus is passed through the tissue and/or creates pockets. The excising assembly is connected to a hand-held control device from which the operator pushes a switch to activate a punching mechanism within the excising assembly. The punching mechanism cuts a discrete piece of muscle tissue and traps it within the excising assembly leaving a pocket in the remaining muscle tissue. The excising assembly may also optionally release a bolus of the pharmacologically active substance into the pocket so created. Most preferably, there is a timing mechanism to measure the contraction of the heart, and the timing mechanism is synchronized with the operator'"'"'s switch on the hand-held device to ensure that the punching occurs at maximum contraction of systole. A measurement guide determines how much excised tissue is trapped in the reservoir of the excising assembly. At a threshold level of filling, the surgeon will remove the excising assembly from the hand-held control device and open the punching mechanism for release of tissue. More preferably, the threshold level of filling will automatically turn off the switch to the punching mechanism to indicate to the surgeon the need to empty the excising assembly of tissue.

Claims

1. An apparatus for creating pockets within muscle tissue, the apparatus comprising:

at least one generally cylindrical excising assembly for entering through and excising muscle tissue having a tapered dilator tip at a distal end; and

a hand-held control means for determining the position and timing of the tissue excision.

2. The apparatus of claim 1 wherein the excising assembly further comprises two semi-dividable shell portions encircling a common central core cylinder running the longitudinal axis of the excising assembly and carrying the insertion means,

where the distal semi-dividable shell portion comprises the tapered dilator tip having a closed surface at its proximal end and sharp edges along the perimeter of said proximal end, and

the proximal semi-dividable shell portion comprises

two encircling cylindrical shell units,

the outer shell unit comprising a hollow cylinder having an open distal end with sharp edges and an open proximal end attached to a connector flange means for connecting the excising assembly to the hand-held control means, and

the inner shell unit comprising a cylindrical shell plunger means, said cylindrical shell plunger means comprising

an outer cylindrical surface lying flush against the inner surface of the outer shell unit,

an inner cylindrical surface lying flush against the outer surface of the central hollow core cylinder,

a closed distal end lying in its relaxed position near the distal end of the outer shell unit, and

a closed proximal end protruding slightly in its relaxed position beyond the proximal side of the connector flange means,

said cylindrical shell plunger means being capable of sliding within the outer shell unit upon pressure applied to either of the shell plunger ends.

3. The excising assembly of claim 2, where by a signal from the hand-held control means, the semi-dividable shell portions separate to let muscle tissue enter into the opening created, and then close rapidly at their sharp edges to operate as a punch to cut the muscle tissue, and wherein the tissue trapped within the excising assembly pushes up against the distal end of the cylindrical shell plunger means, thereby sliding the cylindrical shell plunger means in a proximal direction to protrude further beyond the connector flange means allowing by amount of said protrusion an indication of how much tissue has been trapped within the excising assembly.

4. The apparatus of claim 1 further comprising an optical fiber means that longitudinally runs through the common central core cylinder of the excising assembly having at least one proximal end connected to a source of laser energy and at least one distal end at the tapered end of the dilator tip for advancing the dilator tip through the surface and into the interior of the muscle by thermal damage.

5. The apparatus of claim 3, wherein the semi-dividable shell portions abutting each other with opposing sharp edges can separate to a certain distance of approximately 1 to 9 mm.

6. The apparatus of claim 2 also comprising an insertion means for introducing substances into the pockets created.

7. The apparatus of claim 6 wherein the insertion means comprises a continuous flow mechanism distributing substances at a continuous steady rate.

8. The apparatus of claim 6 wherein the insertion means comprises a pulsed flow mechanism distributing substances in boluses.

9. The apparatus of claim 6 wherein the insertion means comprises both a continuous flow mechanism and a pulsed flow mechanism for distributing substances.

10. The apparatus of claim 6 wherein the substance comprises at least one pharmacologically active ingredient.

11. The apparatus of claim 10 wherein the substance comprises at least one angiogenic factor.

12. The apparatus of claim 10 wherein the substance comprises at least one compound for maintaining the patency of channels or pockets within muscle tissue.

13. The apparatus of claim 1 further comprising a synchronized timing means for sensing contractions and expansions of the beating heart to be synchronized with the hand-held control means for creating the pockets.

14. The apparatus of claim 13 wherein the synchronized timing means is a pressure transducer having a measuring device at its distal end connected to wiring for transmitting the pressure signal, said measuring device located on the surface of the excising assembly and the proximal end of the electrical wiring connected to the hand-held control means.

15. The apparatus of claim 13 wherein the synchronized timing means is an EKG.

16. The apparatus of claim 1 wherein the distance advanced within the organ or muscle is determined by a depth measurement means on the excising assembly.

17. The apparatus of claim 1 wherein the optical fiber means has a diameter of 0.1 to 0.5 mm.

18. The apparatus of claim 1 wherein said optical fiber means is connected to a Holmium HO:

YAG laser source having a wavelength range of approximately 1.8 to 2.2 um and a power level range of approximately 0.2 J to 1.65 J.

19. The apparatus of claim 1 wherein said optical fiber means comprises at least one central optical fiber having a diameter of around 0.2 mm.