Oxygen sensing pacemaker

• US 4,791,935 A
• Filed: 08/15/1986
• Issued: 12/20/1988
• Est. Priority Date: 08/15/1986
• Status: Expired due to Term

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: de Franco, Michael D., Lessar, Joseph F., Bornzin, Gene A., Schweitzer, Jeffrey A., Baudino, Michael D., Brumwell, Dennis A.
• Primary Examiner(s): Jaworski, Francis J.
• Assistant Examiner(s): Manuel, George
• Application Number:
  US06/896,695
• Time in Patent Office: 858 Days
• Field of Search: 128/633, 128/634, 128/785, 128/786, 128/673, 128/675, 128/692
• US Class Current: 600/333
• CPC Class Codes: A61N 1/056 Transvascular endocardial electrode systems
• CPC Class Codes: A61N 1/36557 controlled by chemical substances in blood

Abstract

A heart pacemaker including a two wave length reflectance oximeter for determining oxygen saturation. The pacing rate is increased or decreased in response to the measured oxygen saturation. By appropriate multiplexing and timing functions, the two wave length reflectance oximeter is included in a pacing lead coupled to the pacemaker which requires only three conductors.

Claims

1. An implantable lead comprising:

a sensor capsule having an interior, an exterior surface, a proximal end and a distal end, said sensor capsule comprising a unitary conductive sensor body extending the length of said sensor capsule and exposed to the exterior of said sensor capsule at the proximal and distal ends of said sensor capsule, said sensor capsule further comprising a transparent tubular member, surrounding said sensor body, said tubular member allowing passage of light into the interior of said sensor capsule;

electronic circuitry means for sensor capsule;

electronic circuitry means for sensing a physiologic parameter of the blood by sensing light reflected from said blood, said circuitry means mounted within the interior of said sensor capsule and electrically coupled to said sensor body;

first electrical conductor having a proximal end and a distal end, the distal end of said first conductor coupled to said sensor body at the proximal end of said sensor capsule exterior to the interior of said sensor capsule, the proximal end of said first conductor extending proximally from said sensor capsule;

second electrical conductor, insulated from said first circuitry means;

third electrical conductor having a proximal end and a distal end, the proximal end of said third conductor electrically coupled to said sensor body at the distal and of said sensor capsule exterior to the interior of said sensor capsule, the distal end of said third conductor extending distally from said sensor capsule;

electrode coupled to said third conductor; and

elongated insulative lead body enclosing said first and second conductors, said sensor capsule and said third conductor, said electrode exposed to the exterior of said insulative lead body.

2. A lead according to claim 1 wherein said electronic circuitry means comprises a reflectance oximeter and wherein said insulative lead body is transparent to visible and infrared light.

3. An implantable lead comprising:

a sensor capsule having an interior, an exterior surface, a proximal end and a distal end, said sensor capsule comprising a unitary, conductive sensor body extending the length of said sensor capsule and exposed to the exterior of said sensor capsule at the proximal and distal ends of said sensor capsule;

electronic circuitry means for sensing a physiological parameter of the blood stream, mounted within said sensor capsule and electrically coupled to said sensor body;

first electrical conductor extending proximally from said sensor capsule and electrically coupled to said sensor body at the proximal end of said sensor capsule;

second electrical conductor, insulated from said first conductor and extending proximally from the proximal end of said sensor capsule, said second conductor extending into the interior of said sensor capsule and electrically coupled to said circuitry means;

a third electrical conductor electrically coupled to said sensor body at the digital end of said sensor capsule and extending distally from said sensor capsule;

a fourth electrical conductor, extending proximally from the proximal end of said sensor capsule and extending into the interior of said sensor capsule, insulated from said sensor body and coupled to said circuitry means;

elongated insulative lead body enclosing said first, second and fourth conductors, said sensor capsule and said third conductor with said electrode exposed to the exterior of said insulative lead body; and

wherein said circuitry means comprises a two wavelength reflectance oximeter.

5. A lead according to claim 3 or claim 4 wherein said first conductor comprises an elongated coil conductor having an interior lumen and wherein said second and fourth conductors are located within the lumen of said first conductor.

4. An implantable lead comprising:

a sensor capsule having an interior, an exterior surface, a proximal end and a distal end, said sensor capsule comprising a unitary conductive sensor body extending the length of said sensor capsule and exposed to the exterior of said sensor capsule at the proximal and distal ends of said sensor capsule;

electronic circuitry means for sensing a physiological parameter of the blood stream, mounted within said sensor capsule and electrically coupled to said sensor body;

first elongated electrical conductor extending proximally from said sensor capsule and electrically coupled to said sensor body at the proximal end of said sensor capsule;

second elongated conductor, insulated from said first conductor and extending proximally form the proximal end of said sensor capsule, said second conductor extending into the interior of said sensor capsule and electrically coupled to said circuitry means;

a third conductor electrically coupled to said sensor body at the distal end of said sensor capsule and extending distally from said sensor capsule;

a fourth conductor, extending proximally from the proximal end of said sensor capsule and extending into the interior of said sensor capsule, insluated from said sensor body and coupled to said circuitry means;

elongated insulative lead body enclosing said first, second and fourth conductors, said sensor capsule and said third conductor with said electrode exposed to the exterior of said insulative lead body; and

wherein said electronic circuitry means comprises a two wavelength reflectance oximeter and wherein said circuitry means comprises;

first light emitting diode electrically coupled between said sensor body and said second conductor;

second light emitting diode electrically coupled between said sensor body and said second conductor parallel to but at an opposite polarity to said first light emitting diode; and

a phototransistor coupled between said second and fourth conductors and insulated from said sensor body.