Pacemaker with improved automatic output regulation

• US 4,969,464 A
• Filed: 08/07/1989
• Issued: 11/13/1990
• Est. Priority Date: 03/25/1988
• Status: Expired due to Term

• Current Assignee: Pacesetter Incorporated (Abbott Laboratories Incorporated)
• Original Assignee: Telectronics Incorporated
• Inventors: Vollmann, William, Callaghan, Francis J.
• Primary Examiner(s): Jaworski, Francis
• Assistant Examiner(s): Manuel, George
• Application Number:
  US07/390,528
• Time in Patent Office: 463 Days
• Field of Search: 128/903, 128/904, 128/419 PT, 128/419 PG
• US Class Current: 607/28
• CPC Class Codes: A61N 1/36507 controlled by gradient or slope of the heart potential
• CPC Class Codes: A61N 1/3706 Pacemaker parameters stimulation threshold A61N1/371
• CPC Class Codes: A61N 1/3712 Auto-capture, i.e. automatic adjustment of the stimulation threshold
• CPC Class Codes: Y10S 128/903 Radio telemetry

Abstract

A pacemaker which is provided with an improved automatic regulation circuit which is capable of distinguishing between a fusion beat and loss of capture. The failure to sense an evoked potential following a stimulus may be due to either. The cause is determined by generating a high-energy back-up pulse shortly after the stimulus. Failure to capture by the back-up pulse is an indication that there was just a fusion beat; the sensing of an evoked potential is an indication that the stimulus failed to capture.

Claims

1. A pacemaker for pacing and telemetering fusion beat information comprising means for generating pacing pulses;

means for sensing an evoked potential following generation of a pacing pulse;

said sensing means including means for determining the presence of a fusion beat; and

means responsive to said determining means for generating a fusion beat marker in a telemetry marker channel for transmission of fusion beat information.

2. An implantable pacemaker comprising means for applying pacing pulses to a patient'"'"'s heart;

means for periodically determining the capture threshold of the patient'"'"'s heart;

means responsive to said determining means for adjusting the energy of said pacing pulses to ensure heart capture; and

means for storing values indicative to on-going capture threshold changes over at least the preceding week for telemetering out of the pacemaker.

3. An implantable pacemaker in accordance with claim 2 wherein at least one value is stored for each of at least seven consecutive days.

4. A method of operating a pacemaker for pacing and telemetering fusion beat information comprising the steps of generating pacing pulses;

sensing an evoked potential following generation of one of said pacing pulses;

using the results of said sensing step for determining the presence of a fusion beat; and

, responsive to the determination of the presence of a fusion beat, generating a fusion beat marker in a telemetry marker channel for transmission of fusion beat information.

5. A method of operating an implantable pacemaker comprising the steps of applying pacing pulses to a patient'"'"'s heart;

periodically determining the capture threshold of the patient'"'"'s heart;

responsive to said determining step adjusting the energy of said pacing pulses to ensure heart capture; and

storing values indicative of on-going capture threshold changes over at least the preceding week for telemetering out of the pacemaker.

6. A method of operating an implantable pacemaker in accordance with claim 5 wherein at least one value is stored for each of at least seven consecutive days.