Non-invasive cardiac performance monitoring device and method

• US 5,025,795 A
• Filed: 06/28/1989
• Issued: 06/25/1991
• Est. Priority Date: 06/28/1989
• Status: Expired due to Fees

• Current Assignee: John N. Robinson
• Original Assignee: Horst E. Kunig
• Inventors: Kunig, Horst E.
• Primary Examiner(s): Kamm, William E.
• Assistant Examiner(s): Schaetzle, Kennedy J.
• Application Number:
  US07/373,229
• Time in Patent Office: 727 Days
• Field of Search: 128/704, 128/713, 128/708, 128/700, 128/696, 128/671, 128/716, 128/718
• US Class Current: 600/526
• CPC Class Codes: A61B 5/029 Measuring or recording blood output from the heart, e.g. minute volume A61B8/065 takes precedence
• CPC Class Codes: A61B 5/22 Ergometry; Measuring muscular strength or the force of a muscular blow exercising apparatus A63B21/00 ; measuring of work or force in general G01L
• CPC Class Codes: A61B 5/349 Detecting specific parameters of the electrocardiograph cycle
• CPC Class Codes: A61B 5/355 Detecting T-waves

Abstract

A non-invasive cardiac monitoring device for calculating the cardiac performance parameters of heartbeat, stroke volume, and cardiac output for an individual. The device receives a plurality of electrocardiogram waveform signals from the individual and selects the R-wave component having the maximum value of the electrocardiogram waveform signals and the T-wave component having the maximum value of the electrocardiogram waveforms. From these values, the stroke volume of the individual and the cardiac output of the individual may be calculated according to the equation: Stroke Volume=6×R(max.)/T(max.)+26.0. The periodicity of subsequent electrocardiogram waveforms are utilized to calculate the cardiac performance of the individual.

Claims

1. A non-invasive cardiac monitoring device for determining cardiac pumping performance of an individual, comprising,

means for generating a plurality of electrocardiogram signals indicative of a plurality electrocardiogram waveforms;

means for detecting the amplitude of a R-wave electrocardiogram component having the greatest amplitude from the plurality of the electrocardiogram signals;

means for detecting the amplitude of a T-wave electrocardiogram component having the greatest amplitude from the plurality of electrocardiogram signals;

means responsive to each of the means for detecting for producing a stroke volume signal which is a function of the ratio of the greatest amplitude of the R-wave component to the greatest amplitude of the T-wave component; and

means for displaying values of the stroke volume signal.

2. The non-invasive cardiac monitoring device of claim 1 wherein said stroke volume calculating means generates the stroke volume signal according to the equation:

space="preserve" listing-type="equation">stroke volume=6*R/T+26.0

wherein R/T=the value of the ratio signal generated by the ratio calculating means.

3. A non-invasive cardiac monitoring device according to claim 2 wherein said stroke volume calculating means includes means for generating a signal for monitoring said individual in a cardiac pulmonary rehabilitation program.

4. A non-invasive cardiac monitoring device according to claim 3 further including means responsive to said electrocardiogram sensing means for supplying oxygen enriched air to an individual while exercising in a cardiac pulmonary rehabilitation program.

5. A method to diagnose cardiac performance of an individual, the method including the steps of:

using electrocardiogram sensors on the individual for producing a plurality of electrocardiogram signals corresponding to electrocardiogram waveforms;

selecting a T-wave signal corresponding to the amplitude of the T-wave component having the greatest magnitude from the plurality of electrocardiogram signals;

selecting a R-wave signal corresponding to the amplitude of the R-wave component having the greatest magnitude from the plurality of electrocardiogram signals; and

calculating a value of stroke volume as a function of the ratio of the signals of the selected r-wave component to the selected T-wave component.

7. The method according to claim 5 including the further step of using said stroke volume to generate a signal for a cardiac pulmonary rehabilitation program.

8. The method according to claim 7 including the further step of supplying oxygen enriched air to an individual while said individual is exercising to carry-out a cardiac pulmonary rehabilitation program.

6. The method of claim 6 including the further step of calculating a value of cardiac output by summing successive values of stroke volume over a period of time.

9. A method for monitoring the cardiac performance of an individual in a cardiac pulmonary rehabilitation program comprising the steps of:

using electrocardiogram sensors on the individual for producing a plurality of electrocardiogram signals corresponding to electrocardiogram waveforms;

selecting a T-wave signal corresponding to the amplitude of the T-wave component having the greatest magnitude from the plurality of electrocardiogram signals;

selecting a R-wave signal corresponding to the amplitude of the R-wave component having the greatest magnitude from the plurality of electrocardiogram signals;

calculating a value of stroke volume as a function of the ratio of the signals of the selected R-wave component to the selected T-wave component; and

using said value of stroke volume to generate a signal for monitoring a cardiac pulmonary rehabilitation program for said individual.

10. The method according to claim 9 wherein said step of using said value of stroke volume includes controlling a supply of medication to said individual.

11. The method according to claim 10 wherein said supply of medication includes oxygen enriched air.

12. A non-invasive cardiac monitoring device for determining cardiac pumping performance of an individual, said device comprising:

means for generating a plurality of electrocardiogram signals indicative of a plurality electrocardiogram waveforms;

means for detecting the amplitude of a R-wave electrocardiogram component having the greatest amplitude from the plurality of the electrocardiogram signals;

means for detecting the amplitude of a T-wave electrocardiogram component having the greatest amplitude from the plurality of electrocardiogram signals;

means responsive to each of the means for detecting for producing a stroke volume signal which is a function of the ratio of the greatest amplitude of the R-wave component to the greatest amplitude of the T-wave component;

means for displaying values of the stroke volume signal; and

means for determining a value of cardiac output by summing successive values of stroke volume over a period of time.

13. A method for monitoring the cardiac performance of an individual in a cardiac pulmonary rehabilitation program comprising the steps of:

using electrocardiogram sensors on the individual for producing a plurality of electrocardiogram signals corresponding to electrocardiogram waveforms;

selecting a T-wave signal corresponding to the amplitude of the T-wave component having the greatest magnitude from the plurality of electrocardiogram signals;

selecting a R-wave signal corresponding to the amplitude of the R-wave component having the greatest magnitude from the plurality of electrocardiogram signals;

calculating a value of stroke volume as a function of the ratio of the signals of the selected R-wave component to the selected T-wave component;

using said value of stroke volume including controlling a supply of medication to said individual for monitoring a cardiac pulmonary rehabilitation program for said individual; and

controlling the intensity of exercise performed by said individual during said cardiac pulmonary rehabilitation program.