Method and Apparatus for Acquiring and Analyzing Data Relating to a Physiological Condition of a Subject

• US 20110263994A1
• Filed: 12/11/2008
• Published: 10/27/2011
• Est. Priority Date: 12/13/2007
• Status: Abandoned Application

• Current Assignee: Heart Force Medical, Inc.
• Original Assignee: Heart Force Medical, Inc.
• Inventors: Miller, Mark, MacQuarrie, David, Jahns, Graeme, Rotherie, Kimora, Windels, Max, Lancaster, David, Burns, James Alexander
• Application Number:
  US12/747,891
• Publication Number:
  US 20110263994A1
• Time in Patent Office: Days
• US Class Current: 600/509
• CPC Class Codes: A61B 2560/0412 Low-profile patch shaped housings
• CPC Class Codes: A61B 2560/045 with a separable interface unit, e.g. for communication
• CPC Class Codes: A61B 2562/0219 Inertial sensors, e.g. accelerometers, gyroscopes, tilt switches
• CPC Class Codes: A61B 5/0006 ECG or EEG signals
• CPC Class Codes: A61B 5/02028 Determining haemodynamic parameters not otherwise provided for, e.g. cardiac contractility or left ventricular ejection fraction
• CPC Class Codes: A61B 5/1102 Ballistocardiography
• CPC Class Codes: A61B 5/339 Displays specially adapted therefor
• CPC Class Codes: A61B 5/6833 Adhesive patches

Abstract

A method for locating and marking points on a waveform includes providing data corresponding to electrocardiogram and ballistocardiogram waveforms correlated in time, searching the data to locate points corresponding to cardiac events, a location of each of the points corresponding to cardiac events being defined by a rule set, identifying and storing the points corresponding to cardiac events and outputting a visual representation including the points corresponding to cardiac events marked on the electrocardiogram and ballistocardiogram waveforms.

Claims

1-9. -9. (canceled)

10. An apparatus for acquiring and analyzing data relating to a physiological condition of a subject, said apparatus comprising:

a sensor device for coupling to said subject, said sensor device for detecting four analog signals, one of said four analog signals being an electrocardiograph signal and three of said four analog signals being ballistocardiograph signals, converting said four analog signals to digital signals and transmitting said digital signals; and

a computer including a processor in communication with said sensor device, said computer configured for receiving and analysing data representative of said digital signals and for generating a report relating to said physiological condition of said subject.

12. The apparatus as claimed in claim 10, wherein said sensor device comprises a three-axis accelerometer for detecting said ballistocardiograph signals and wherein each of said ballistocardiograph signals corresponds to an axis of said three axis accelerometer.

13. The apparatus as claimed in claim 10, wherein said sensor device comprises a pair of conductive strips in communication with electrocardiograph lead circuitry for detecting said electrocardiograph signals.

14. The apparatus as claimed in claim 10, wherein said computer is configured for communicating with said sensor device to control detection of said four analog signals.

15. The apparatus as claimed in claim 10, further comprising a portable terminal in communication with said sensor device and said computer, said portable terminal for controlling detection of said four analog signals, for receiving said digital signals from said sensor device and for transmitting data representative of said digital signals to said computer.

16. The apparatus as claimed in claim 15, wherein said portable terminal is configured for receiving subject identification information and associating said subject identification information with said digital signals.

17. The apparatus as claimed in claim 16, wherein said portable terminal includes a device for reading an electronic code, said electronic code including said subject identification information.

18. The apparatus as claimed in claim 10, wherein said computer is a portable terminal.

19. The apparatus as claimed in claim 18, wherein said portable terminal is configured for receiving subject identification information and associating said subject identification information with said digital signals.

20. The apparatus as claimed in claim 19, wherein said portable terminal includes a device for reading an electronic code, said electronic code including said subject identification information.

21. The apparatus as claimed in claim 10, wherein said computer is in communication with said sensor device via a wireless connection.

22. The apparatus as claimed in claim 10, wherein said computer is in communication with said sensor device via a wired connection.

23. The apparatus as claimed in claim 15, wherein said portable terminal is in communication with said sensor device and/or said computer via a wireless connection.

24. The apparatus as claimed in claim 10, wherein the computer is configured for applying a rule set to data corresponding to electrocardiogram and ballistocardiogram waveforms correlated in time, said electrocardiogram and ballistocardiogram waveforms correlated in time generated from said digital signals, said rule set including parameters for locating points corresponding to cardiac events on said electrocardiogram and ballistocardiogram waveforms.

25. The apparatus as claimed in claim 24, wherein said computer is further configured for storing said points corresponding to cardiac events with said data corresponding to electrocardiogram and ballistocardiogram waveforms correlated in time.

26. The apparatus as claimed in claim 24, wherein the report comprises a representation of said points corresponding to cardiac events located on said electrocardiogram and ballistocardiogram waveforms.

27. The apparatus as claimed in claim 24, wherein said parameters are selected from the group consisting of:

time interval from one of said points corresponding to cardiac events, a valley on a ballistocardiogram waveform, a peak on a ballistocardiogram waveform, intersection of two ballistocardiogram waveforms, slope direction of a ballistocardiogram waveform and change of slope of a ballistocardiogram waveform.

28. The apparatus as claimed in claim 24, wherein said cardiac events are selected from the group consisting of:

depolarization of the inter-ventricular septum (Q), atrial contraction (G), mitral valve close (H), isovolumic movement (I), rapid ejection period(J), aortic valve open (AVO), aortic valve close (AVC) and mitral valve open (M).

29. The apparatus as claimed in claim 10, further comprising an input device for receiving cardiac event identification input to produce an annotated heart beat, said input device in communication with said computer;

wherein said computer is configured for annotating electrocardiogram and ballistocardiogram waveforms by applying a template generated based on said cardiac event identification input, said electrocardiogram and ballistocardiogram waveforms correlated in time generated from said digital signals.

30. The apparatus as claimed in claim 29, wherein the report comprises a representation of annotated electrocardiogram and ballistocardiogram waveforms correlated in time.

31. The apparatus as claimed in claim 29, wherein said cardiac event identification input includes a reference event and other cardiac events.

32. The apparatus as claimed in claim 31, wherein said reference event is depolarization of the inter-ventricular septum (Q) or ventricular activation (R).

33. The apparatus as claimed in claim 31, wherein said other cardiac events are selected from the group consisting of:

atrial contraction (G), mitral valve close (H), isovolumic movement (I), rapid ejection period (J), aortic valve open (AVO), aortic valve close (AVC) and mitral valve open (M).

34. A method for acquiring and analyzing data relating to a physiological condition of a subject, said method comprising:

detecting four analog signals using a sensor device coupled to said subject, one of said four analog signals being an electrocardiograph signal and three of said four analog signals being ballistocardiograph signals,

converting said four analog signals into digital signals;

transmitting data representative of said digital signals to a computer; and

performing an analysis of said data representative of said digital signals.

35. The method as claimed in claim 34, further comprising generating and outputting a report relating to said physiological condition.

36. The method as claimed in claim 34, wherein the ballistocardiograph signals are detected using a three-axis accelerometer comprised by said sensor.

37. The method as claimed in claim 34, further comprising providing commands to said sensor device to control detection of said four analog signals.

38. The method as claimed in claim 37, wherein said commands are provided by said computer, or by a portable terminal in communication with said sensor device and said computer.

39. The method as claimed in claim 34, further comprising associating subject identification information with said digital signals.

40. A sensor device for acquiring and transmitting signals relating to a physiological condition of a subject, said sensor device comprising:

a housing including a contact surface for coupling to a subject;

a three-axis accelerometer provided in said housing, said three-axis accelerometer for sensing vibrations of a chest wall of said subject;

conductive strips provided in said contact surface of said housing, said conductive strips being in communication with electrocardiograph lead circuitry for sensing cardiac electrical activity;

an analog to digital converter in communication with said three-axis accelerometer and said electrocardiograph lead circuitry, said analog to digital converter for receiving four analog signals, one of said four analog signals being an electrocardiograph signal and three of said four analog signals being ballistocardiograph signals corresponding to each axis of said three-axis accelerometer, and for converting said four analog signals into digital signals;

a power source; and

a transmitter provided in communication with said analog to digital converter for transmitting said digital signals.

41. The sensor device as claimed in claim 40, wherein one or more of said analog to digital converter, said power source and said transmitter are provided in said housing.

42. The sensor device as claimed in claim 40, wherein said transmitter is a radio device for wireless communication.

43. The sensor device as claimed in claim 40, wherein said transmitter transmits said digital signals to a computer or a portable terminal.

44. A method for locating and marking points on a waveform comprising:

providing data corresponding to electrocardiogram and ballistocardiogram waveforms correlated in time;

searching said data to locate points corresponding to cardiac events, a location of each of said points corresponding to cardiac events being defined by a rule set;

identifying said points corresponding to cardiac events; and

outputting a report comprising a representation of said points corresponding to cardiac events located on said electrocardiogram and ballistocardiogram waveforms.

45. The method as claimed in claim 44, wherein said rule set includes rules in which a location of each of said points corresponding to cardiac events is defined by at least one parameter.

46. The method as claimed in claim 45, wherein said at least one parameter is selected from the group consisting of:

time interval from one of said points corresponding to cardiac events, a valley on a ballistocardiogram waveform, a peak on a ballistocardiogram waveform, intersection of two ballistocardiogram waveforms, slope direction of a ballistocardiogram waveform and change of slope of a ballistocardiogram waveform.

47. The method as claimed in claim 44, wherein said cardiac events are selected from the group consisting of:

depolarization of the inter-ventricular septum (Q), atrial contraction (G), mitral valve close (H), isovolumic movement (I), rapid ejection period(J), aortic valve open (AVO), aortic valve close (AVC) and mitral valve open (M).

48. A computer-readable medium comprising instructions executable on a processor of a computer for implementing the method of claim 44.

49. A method for locating and marking points on a waveform comprising:

providing electrocardiogram and ballistocardiogram waveform data correlated in time and extending for at least two heart beats, one of said at least two heart beats being an annotated heart beat having cardiac events identified thereon, said cardiac events including a reference event located on an electrocardiogram waveform;

generating a template based on said annotated heart beat, said template including time intervals measured from said reference event to one or more other identified cardiac events; and

locating said reference event on one or more heart beats other than said annotated heart beat and applying said template to determine locations of said other cardiac events thereon.

50. The method as claimed in claim 49, further comprising optimizing a location of one or more of said other cardiac events.

51. The method as claimed in claim 50, wherein said location of said one or more of said other cardiac events is optimized by applying a rule.

52. The method as claimed in claim 51, wherein said rule moves a previously determined location of said one or more of said other cardiac events to an optimized location that coincides with a landmark located within a time window extending on either side of said previously determined location.

53. The method as claimed in claim 52, wherein said landmark is selected from the group consisting of:

lowest point on a ballistocardiogram waveform, highest point on a ballistocardiogram waveform, intersection of two ballistocardiogram waveforms and smallest distance between two ballistocardiogram waveforms.

54. The method as claimed in claim 52, wherein said time window is about +/−

10 ms.

55. The method as claimed in claim 49, wherein said reference event is depolarization of the inter-ventricular septum (Q) or ventricular activation (R).

56. The method as claimed in claim 49, wherein said other cardiac events are selected from the group consisting of:

atrial contraction (G), mitral valve close (H), isovolumic movement (I), rapid ejection period (J), aortic valve open (AVO), aortic valve close (AVC) and mitral valve open (M).

57. A computer-readable medium comprising instructions executable on a processor of a computer for implementing the method of claim 49.