IMPLANTABLE MEDICAL DEVICE HAVING OPTICAL FIBER FOR SENSING ELECTRICAL ACTIVITY

• US 20080200769A1
• Filed: 02/16/2007
• Published: 08/21/2008
• Est. Priority Date: 02/16/2007
• Status: Active Grant

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Zhou, Xiaohong, SHARMA, VINOD
• Granted Patent: US 8,396,539 B2
• Time in Patent Office: Days
• US Class Current: 600/300
• CPC Class Codes: A61B 5/0071 by measuring fluorescence emission
• CPC Class Codes: A61B 5/0084 for introduction into the body, e.g. by catheters A61B5/1459 takes precedence
• CPC Class Codes: A61B 5/349 Detecting specific parameters of the electrocardiograph cycle

Abstract

An implantable medical device for optically sensing action potential signals in excitable body tissue. The device includes an elongated tubular lead body carrying an optical fiber extending from a proximal lead end to a distal lead end to position the optical fiber at a target site. The lead body additionally carries a conduit for dispensing a voltage-sensitive fluorescent dye into tissue surrounding the target site. The optical fiber transmits excitation light to the fluorescent dye to cause the dye to fluoresce with varying intensity as the transmembrane potentials of local tissue cells vary due to passing depolarization wavefronts. The optical fiber transmits the fluorescence signal to the device to generate an action potential signal or fiducial points of an action potential signal for use in accurately measuring and characterizing electrical activity of excitable tissue.

Claims

1. A method for monitoring of gene expression corresponding to a target site in a patient, the method comprising:

co-transfecting tissue with a marker gene and a therapeutic gene; and

monitoring expression of one of the marker gene and the therapeutic gene.

2. A method for monitoring of infarct mapping for cell/gene delivery corresponding to a target site in a patient, the method comprising:

determining an infarction has occurred; and

mapping an infarct.

3. A method for monitoring of cell/gene delivery corresponding to a target site in a patient, the method comprising:

transfecting a cell with fluorescent marker; and

monitoring the cell delivered to the tissue.

4. A method for monitoring of a multifiber system in a patient, the method comprising:

exciting tissue; and

collecting of emitted light from the excited tissue.

5. The method of claim 4, wherein the multifiber system simultaneously maps electrical activity of both an infarcted tissue and tissue adjacent to the infarcted tissue.

6. A method for enhancing a field of view corresponding to a target site in a patient, the method comprising:

accessing a fiber umbrella; and

monitoring electrical activity associated with the target site through the fiber umbrella.

7. A method for detecting light associated from a single fiber of a bundle of fibers, the method comprising:

providing a switching mechanism;

selecting a first channel of light associated with a first fiber;

using the switching mechanism to switch to a second channel of light associated with a second fiber; and

collecting light from both the first and the second channels.

8. The method of claim 7, wherein the switching mechanism comprises a mirror for a collector of signals.

9. A method for detecting light associated from a single fiber of a bundle of fibers, the method comprising:

transmitting excitation light from a single fiber of a fiber bundle; and

collecting emitted light from the single fiber.

10. The method of claim 9, wherein the emitted light being fluorescent light.

11. A method for voltage activity corresponding to a target site in a patient, the method comprising:

transfecting cells with a protein;

encoding the cells with a voltage sensitive protein; and

monitoring the voltage activity associated with the cells.