Systems and methods for electrosurgical myocardial revascularization

• US 5,860,951 A
• Filed: 11/22/1996
• Issued: 01/19/1999
• Est. Priority Date: 01/07/1992
• Status: Expired due to Term

• Current Assignee: ArthroCare Corporation (Smith & Nephew PLC)
• Original Assignee: ArthroCare Corporation (Smith & Nephew PLC)
• Inventors: Eggers, Philip E., Thapliyal, Hira V.
• Primary Examiner(s): MENDEZ, MANUEL A
• Application Number:
  US08/753,226
• Time in Patent Office: 788 Days
• Field of Search: 604/113, 604/114, 604/22, 604/41, 606/27-32, 606/35, 606/38, 606/41
• US Class Current: 604/510
• CPC Class Codes: A61B 18/12 by passing a current through the tissue to be heated, e.g. high-frequency current
• CPC Class Codes: A61B 18/1206 Generators therefor
• CPC Class Codes: A61B 18/1402 Probes for open surgery
• CPC Class Codes: A61B 18/148 having a short, rigid shaft for accessing the inner body transcutaneously, e.g. for neurosurgery or arthroscopy
• CPC Class Codes: A61B 18/1482 having a long rigid shaft for accessing the inner body transcutaneously in minimal invasive surgery, e.g. laparoscopy
• CPC Class Codes: A61B 18/1485 having a short rigid shaft for accessing the inner body through natural openings
• CPC Class Codes: A61B 18/149 bow shaped or with rotatable body at cantilever end, e.g. for resectoscopes, or coagulating rollers
• CPC Class Codes: A61B 18/1492 having a flexible, catheter-like structure, e.g. for heart ablation A61B18/1477 takes precedence
• CPC Class Codes: A61B 2017/00026 Conductivity or impedance, e.g. of tissue
• CPC Class Codes: A61B 2017/00084 Temperature
• CPC Class Codes: A61B 2017/00097 one of the thermometric elements being an electrode or the heating element
• CPC Class Codes: A61B 2017/00101 using an array of thermosensors
• CPC Class Codes: A61B 2017/00106 ultrasonic
• CPC Class Codes: A61B 2017/00247 Making holes in the wall of the heart, e.g. laser Myocardial revascularization
• CPC Class Codes: A61B 2017/00292 mounted on or guided by flexible, e.g. catheter-like, means
• CPC Class Codes: A61B 2017/003 Steerable
• CPC Class Codes: A61B 2017/22001 Angioplasty, e.g. PCTA
• CPC Class Codes: A61B 2017/22038 with a guide wire
• CPC Class Codes: A61B 2018/00029 open
• CPC Class Codes: A61B 2018/00083 low, i.e. electrically insulating
• CPC Class Codes: A61B 2018/00119 : with metal oxide nitride
• CPC Class Codes: A61B 2018/0016 : Energy applicators arranged in a two- or three dimensional array
• CPC Class Codes: A61B 2018/00178 : Electrical connectors
• CPC Class Codes: A61B 2018/00196 : reciprocating lengthwise
• CPC Class Codes: A61B 2018/00327 : Ear, nose or throat
• CPC Class Codes: A61B 2018/00392 : Transmyocardial revascularisation
• CPC Class Codes: A61B 2018/00505 : Urinary tract
• CPC Class Codes: A61B 2018/00577 : Ablation
• CPC Class Codes: A61B 2018/00583 : Coblation, i.e. ablation using a cold plasma
• CPC Class Codes: A61B 2018/00601 : Cutting
• CPC Class Codes: A61B 2018/00642 : with feedback, i.e. closed loop control
• CPC Class Codes: A61B 2018/0066 : without feedback, i.e. open loop control
• CPC Class Codes: A61B 2018/00678 : upper
• CPC Class Codes: A61B 2018/00702 : Power or energy
• CPC Class Codes: A61B 2018/00726 : Duty cycle
• CPC Class Codes: A61B 2018/00738 : Depth, e.g. depth of ablation
• CPC Class Codes: A61B 2018/00755 : Resistance or impedance
• CPC Class Codes: A61B 2018/00761 : Duration
• CPC Class Codes: A61B 2018/00791 : Temperature
• CPC Class Codes: A61B 2018/00797 : measured by multiple temperature sensors
• CPC Class Codes: A61B 2018/00821 : measured by a thermocouple
• CPC Class Codes: A61B 2018/00827 : Current
• CPC Class Codes: A61B 2018/00875 : Resistance or impedance
• CPC Class Codes: A61B 2018/00886 : Duration
• CPC Class Codes: A61B 2018/00982 : combined with or comprising means for visual or photographic inspections inside the body, e.g. endoscopes
• CPC Class Codes: A61B 2018/1213 : creating an arc
• CPC Class Codes: A61B 2018/124 : switching the output to different electrodes, e.g. sequentially
• CPC Class Codes: A61B 2018/1246 : characterised by the output polarity
• CPC Class Codes: A61B 2018/1253 : monopolar
• CPC Class Codes: A61B 2018/126 : bipolar
• CPC Class Codes: A61B 2018/1273 : including multiple generators in one device
• CPC Class Codes: A61B 2018/1407 : Loop
• CPC Class Codes: A61B 2018/1467 : using more than two electrodes on a single probe
• CPC Class Codes: A61B 2018/1472 : for use with liquid electrolyte, e.g. virtual electrodes
• CPC Class Codes: A61B 2018/1497 : Electrodes covering only part of the probe circumference
• CPC Class Codes: A61B 2018/162 : located on the probe body
• CPC Class Codes: A61B 2018/165 : Multiple indifferent electrodes
• CPC Class Codes: A61B 2090/378 : using ultrasound
• CPC Class Codes: A61B 2090/3782 : transmitter or receiver in catheter or minimal invasive instrument
• CPC Class Codes: A61B 2218/002 : Irrigation
• CPC Class Codes: A61B 2218/007 : Aspiration
• CPC Class Codes: A61F 2/2493 : Transmyocardial revascularisation [TMR] devices
• CPC Class Codes: A61F 2/95 : Instruments specially adapted for placement or removal of stents or stent-grafts
• CPC Class Codes: A61M 25/0133 : Tip steering devices
• CPC Class Codes: A61M 25/0147 : with movable mechanical means, e.g. pull wires
• CPC Class Codes: A61M 25/0158 : with magnetic or electrical means, e.g. by using piezo materials, electroactive polymers, magnetic materials or by heating of shape memory materials

Abstract

A method for transmyocardial revascularization of the heart of a patient includes positioning an active electrode surface in close proximity to a target site on the wall of a patient'"'"'s heart, and applying high frequency voltage between the active voltage surface and a return electrode to ablate tissue at the heart wall. The high frequency voltage ablates, i.e. volumetrically removes the heart tissue, and the electrode surface is axially translated into the space vacated by the removed tissue to bore a channel through the heart tissue. The active electrode surface may be introduced into the thoracic cavity and placed adjacent the epicardium to form an inward channel toward the ventricular cavity, or it may be delivered into the ventricular cavity of the heart and positioned adjacent the endocardium to form a channel extending outward towards the epicardium. In either case, the channels formed through the myocardium promote direct communication between blood within the ventricular cavity and that of existing myocardial vasculature to increase blood flow to the heart tissue.

Claims

1. A method of transmyocardial revascularization of the heart of a patient comprising:

forming a revascularizing channel through a portion of the heart with high frequency electrical energy, the revascularizing channel extending through an exterior heart wall into the myocardium; and

positioning a radially expandable lumenal prosthesis within the revascularizing channel to maintain patency of the channnel.

2. The method of claim 1 wherein the forming step is carried out by:

positioning an active electrode surface in close proximity to a target site on a wall of the patient'"'"'s heart; and

applying high frequency voltage between the active electrode surface and a return electrode to ablate tissue at the heart wall and to form a revascularizing channel through at least a portion of the heart wall.

3. The method of claim 2 wherein the positioning step comprises endoluminally delivering a tubular stent to the revascularizing channel and radially expanding the tubular stent against the walls of said channel to maintain lumen patency.

4. The method of claim 3 wherein the radially expanding step comprises expanding a balloon within an axial lumen of the stent to radially expand a tubular frame of the stent.

5. The method of claim 3 wherein the radially expanding step comprises compressing the stent frame into a radially compressed configuration, and allowing the stent frame to recover to an expanded configuration within the revascularizing channel.

6. The method of claim 5 wherein the allowing step is carried out by the application of heat from the patient'"'"'s body.

7. The method of claim 1 wherein the revascularizing channel has an endpoint within the myocardium.

8. The method of claim 1 wherein the revascularizing channel extends completely through the heart wall between an exterior portion of the heart and a ventricle within the heart.

9. A system for transmyocardial revascularization of the heart of a patient comprising:

an electrosurgical instrument having a shaft with proximal and distal ends, one or more active electrodes disposed near the distal end of the shaft and a connector disposed near the proximal end of the shaft for electrically coupling the electrodes to a high frequency voltage source;

a return electrode positioned near the active electrodes for;

a connector disposed near the proximal end of the shaft for electrically coupling the active and return electrodes to a high frequency voltage source to ablate tissue at the heart wall and to form one or more revascularizing channels through at least a portion of the heart wall into the myocardium; and

a delivery mechanism for implanting one or more lumenal prosthesis into the revascularizing channels formed by the electrosurgical instrument.

10. The system of claim 9 wherein the delivery mechanism is integral with the instrument shaft.

11. The system of claim 9 further comprising a delivery catheter separate from the electrosurgical probe for endoluminally delivering and implanting the lumenal prostheses within the revascularizing channels.

12. The system of claim 9 further comprising means for radially expanding the lumenal prostheses to engage the inner walls of the revascularizing channels to maintain lumen patency.

13. The system of claim 12 wherein the radially expanding means comprises an expandable member configured for positioning within an axial lumen of the prostheses.

14. The system of claim 12 wherein the lumenal prostheses comprise shape memory alloy material having an A_f temperature below body temperature.

15. The system of claim 9 wherein the revascularizing channels each have an endpoint within the myocardium.

16. The system of claim 9 wherein the revascularizing channels extend completely through the heart wall between an exterior portion of the heart and a ventricle within the heart.