System for Cardiac Pathology Detection and Characterization

• US 20100312125A1
• Filed: 04/06/2010
• Published: 12/09/2010
• Est. Priority Date: 06/05/2009
• Status: Active Grant

• Current Assignee: PixArt Imaging Incorporated
• Original Assignee: Siemens Medical Solutions USA Incorporated (Siemens AG)
• Inventors: Zhang, Hongxuan
• Granted Patent: US 10,064,560 B2
• Time in Patent Office: Days
• US Class Current: 600/485
• 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 5/021 Measuring pressure in heart or blood vessels A61B5/0205 takes precedence
• CPC Class Codes: A61B 5/02116 of pulse wave amplitude A61B5/02225 takes precedence
• CPC Class Codes: A61B 5/02158 provided with two or more sensor elements
• CPC Class Codes: A61B 5/7257 using Fourier transforms

Abstract

A system for heart performance characterization and abnormality detection includes an interface for receiving digitized electrical signals representing blood pressure waveforms over one or more heart beat cycles. The digitized electrical signals comprise, a first digital data sequence representing normal blood pressure of a patient, a second digital data sequence representing random blood pressure of a normal patient and a third digital data sequence representing a potentially abnormal blood pressure of a patient. A complexity processor calculates first, second and third complexity indices for the corresponding first, second and third digital data sequences respectively. A correlation processor uses the calculated first, second and third complexity indices to calculate one or more measures indicating deviation of the potentially abnormal blood pressure of the patient from a normal value.

Claims

1. A system for heart performance characterization and abnormality detection, comprising:

an interface for receiving digitized electrical signals representing blood pressure waveforms over one or more heart beat cycles comprising,

a first digital data sequence representing normal blood pressure of a patient,

a second digital data sequence representing random blood pressure of a normal patient and

a third digital data sequence representing a potentially abnormal blood pressure of a patient; and

a complexity processor for calculating first, second and third complexity indices for the corresponding first, second and third digital data sequences respectively; and

a correlation processor for using the calculated first, second and third complexity indices to calculate one or more measures indicating deviation of said potentially abnormal blood pressure of said patient from a normal value.

2. A system according to claim 1, wherein

said interface substantially synchronizes the first, second and third digital data sequences.

3. A system according to claim 2, wherein

said interface substantially synchronizes the first, second and third digital data sequences in response to a peak or minimum value in the corresponding blood pressure waveforms.

4. A system according to claim 1, wherein

said first, second and third complexity indices comprise S_i, S_R and S_j respectively and said correlation processor calculates at least one of (a) C(s_j)−

C(s′

_R) representing the complexity distance (nonlinearity) from a current blood pressure waveform to a random waveform and (b) C(s_i)−

C(s_R) representing a complexity distance from a normal (baseline) pressure waveform to a random waveform.

5. A system according to claim 4, wherein

said correlation processor calculates ratio of (a) and (b).

6. A system according to claim 1, including

a data processor for monitoring said first, second and third complexity indices or values derived from these indices and in response to indices and values derived from these indices or a variation in the indices and values derived from these indices exceeding a predetermined threshold, generating an alert message.

7. A system according to claim 6, wherein

said data processor substantially continuously performs the monitoring for at least a 24 hour period.

8. A system according to claim 6, wherein

said data processor uses predetermined mapping information, associating ranges of said indices or values derived from these indices with corresponding medical conditions, in comparing said indices or values derived from these indices with said ranges and generates an alert message indicating a potential medical condition.

9. A system according to claim 8, wherein

said predetermined mapping information associates ranges of said indices or values derived from these indices with particular patient demographic characteristics and with corresponding medical conditions and said data processor uses patient demographic data including at least one of age weight, gender and height in comparing said indices or values derived from these indices with said ranges and generating an alert message indicating a potential medical condition.

10. A system according to claim 8, wherein

said first digital data sequence representing normal blood pressure of a patient is provided from stored blood pressure data of at least one of (a) said patient and (b) a patient having similar demographic characteristics as said patient including at least one of, age weight, gender and height and similar medical conditions as said patient.

11. A method for heart performance characterization and abnormality detection, comprising the activities of:

receiving digitized electrical signals representing blood pressure waveforms over one or more heart beat cycles comprising,

a first digital data sequence representing normal heart blood pressure of a patient,

a second digital data sequence representing random heart blood pressure of a normal patient and

a third digital data sequence representing a potentially abnormal heart blood pressure of a patient; and

calculating first, second and third complexity indices for the corresponding first, second and third digital data sequences respectively; and

using the calculated first, second and third complexity indices to calculate one or more measures indicating deviation of said potentially abnormal heart blood pressure of said patient from a normal range.

12. A system for heart performance characterization and abnormality detection, comprising:

an interface for receiving a digitized electrical signal representing a blood pressure waveform over one or more heart beat cycles;

a data processor for performing a Fourier transform on said digitized electrical signal to derive data representing individual frequency components of said digitized electrical signal;

a calculation processor for determining measures comprising,

(a) a first value representing a summation of the square of individual Fourier transform values of corresponding individual components of said individual frequency components and

(b) a second value representing a square of the summation of individual Fourier transform values of corresponding individual components of said individual frequency components; and

a correlation processor for using the calculated first and second values to calculate one or more measures indicating deviation of said potentially abnormal blood pressure of said patient from a normal value.

13. A system according to claim 12, wherein

said interface synchronizes said digitized electrical signal.

14. A system according to claim 13, wherein

said interface substantially synchronizes said digitized electrical signal in response to a peak or minimum value in the corresponding blood pressure waveforms.

15. A system according to claim 12, wherein

said correlation processor calculates a ratio employing said first and second values in deriving a measure indicating deviation of said potentially abnormal blood pressure of said patient from a normal value.

16. A system according to claim 15, wherein

said correlation processor calculates a ratio employing said first and second values comprising,

17. A system according to claim 15, wherein

said correlation processor calculates a ratio employing said first and second values comprising,