System for Cardiac Status Determination

• US 20110190643A1
• Filed: 10/19/2010
• Published: 08/04/2011
• Est. Priority Date: 02/04/2010
• Status: Active Grant

• Current Assignee: Siemens Healthcare GMBH (Siemens AG)
• Original Assignee: Siemens Medical Solutions USA Incorporated (Siemens AG)
• Inventors: Mukundhan, Prabhu, Zhang, Hongxuan
• Granted Patent: US 8,668,649 B2
• Time in Patent Office: Days
• US Class Current: 600/486
• CPC Class Codes: A61B 5/0205 Simultaneously evaluating both cardiovascular conditions and different types of body conditions, e.g. heart and respiratory condition
• CPC Class Codes: A61B 5/021 Measuring pressure in heart or blood vessels A61B5/0205 takes precedence
• CPC Class Codes: A61B 5/0215 by means inserted into the body catheters A61M25/00
• CPC Class Codes: A61B 5/02405 Determining heart rate variability
• CPC Class Codes: A61B 5/349 Detecting specific parameters of the electrocardiograph cycle
• CPC Class Codes: A61B 5/7275 Determining trends in physiological measurement data; Predicting development of a medical condition based on physiological measurements, e.g. determining a risk factor
• CPC Class Codes: G16H 50/20 for computer-aided diagnosis, e.g. based on medical expert systems
• CPC Class Codes: G16H 50/30 for calculating health indices; for individual health risk assessment

Abstract

A system improves detection and diagnosis of blood pressure based cardiac function and tissue activities by analyzing and characterizing cardiac blood pressure signals (including non-invasive and invasive blood pressure, discrete values and continuous waveforms) using pressure signal variation and variability calculation and evaluation. The system combines blood pressure analysis with multi clinical related factors and parameters to detect and quantify cardiac health status and arrhythmia severity. The system determines an accurate time, location and severity of cardiac pathology and events by calculating blood pressure variability and statistical variation. The accurately and reliably identifies cardiac disorders, differentiates cardiac arrhythmias, characterizes pathological severity, predicts the life-threatening events, and supports evaluation of drug delivery effects.

Claims

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

an interface for receiving a set of sampled data values representing patient blood pressure occurring during individual heart cycles of a plurality of sequential heart cycles;

a signal processor for generating a mathematical distribution using the received sampled data set and calculating,

(a) a first value substantially comprising an average of the sampled data set,

(b) a second value substantially comprising a distribution value at a first deviation point from the average of the data set and

(c) a ratio of the first and second value as a representation of blood pressure variation; and

a comparator for comparing said ratio with a threshold value to provide a comparison indicator; and

a patient monitor for in response to said comparison indicator indicating said ratio exceeds the threshold value, generating an alert message associated with the threshold.

2. A system according to claim 1, wherein

said plurality of sequential heart cycles are successive heart cycles.

3. A system according to claim 1, wherein

said average of the sampled data set comprises at least one of, (a) an arithmetic mean, (b) a median and (c) a root mean square value.

4. A system according to claim 1, wherein

said second value substantially comprises a standard deviation value of the dataset.

5. A system according to claim 1, wherein

said signal processor generates a third value substantially comprising a distribution value at a second deviation point from the average of the data set.

6. A system according to claim 5, wherein

said signal processor generates a ratio of a difference between the first and second values and a difference between the second and third values as representation of blood pressure variation.

7. A system according to claim 5, wherein

said second deviation point is substantially twice the deviation from the average of the data set as the first deviation point.

8. A system according to claim 1, wherein

said blood pressure comprises at least one of, (a) an intra-cardiac blood pressure, (b) a systolic blood pressure, (c) a diastolic blood pressure, (d) an invasive blood pressure and (e) a non-invasive blood pressure.

9. A system according to claim 1, wherein

said comparator determines a comparison indicator indicating whether said ratio lies in a predetermined value range and

said patient monitor, in response to said comparison indicator indicating said ratio lies in a predetermined value range, generates an alert message associated with the value range.

10. A system according to claim 1, wherein

said threshold value is derived from recorded blood pressure data for said patient.

11. A system according to claim 1, wherein

said threshold value is derived from recorded blood pressure data for a population of patients having similar demographic characteristics including at least two of, (a) age, (b) weight, (c) gender and (d) height, to those of said patient.

12. A system according to claim 1, wherein

said signal processor dynamically adjusts said threshold value in response to a determined blood pressure variation of said patient.

13. A system according to claim 1, wherein

said mathematical distribution comprises at least one of (a) a Gaussian distribution, (b) a normal distribution, (c) an Autoregression distribution model and (d) an Autoregression and Moving Average distribution model.

14. A system according to claim 1, including

a repository of mapping information, associating ranges of the ratio with corresponding medical conditions and

said comparator compares said ratio with said ranges to provide a comparison indicator identifying a medical condition and

said patient monitor generates an alert message identifying said medical condition.

15. A system according to claim 14, wherein

said predetermined mapping information associates ranges of the ratio with particular patient demographic characteristics and with corresponding medical conditions and said system uses patient demographic data including at least one of, age weight, gender and height in comparing the ratio with said ranges and generating an alert message indicating a potential medical condition.

16. A system according to claim 1, wherein

said first value and said second value comprise amplitude values.

17. A method employed by at least one processing device for heart performance characterization and abnormality detection, comprising the activities of:

receiving a set of sampled data values representing patient blood pressure occurring during individual heart cycles of a plurality of sequential heart cycles;

generating a mathematical distribution using the received sampled data set and calculating,

(a) a first value substantially comprising a distribution value at a first deviation point from the average of the data set,

(b) a second value substantially comprising a distribution value at a first deviation point from the average of the data set and

(c) a ratio of the first and second value as a representation of blood pressure variation; and

comparing said ratio with a threshold value to provide a comparison indicator; and

in response to said comparison indicator indicating said ratio exceeds the threshold value, generating an alert message associated with the threshold.

18. A method employed by at least one processing device for heart performance characterization and abnormality detection, comprising the activities of:

receiving a set of sampled data values representing patient blood pressure occurring during individual heart cycles of a plurality of sequential heart cycles;

generating a spectrum from the received sampled data set and calculating,

(a) a first value substantially comprising a frequency spectrum value at a first peak point,

(b) a second value substantially comprising a frequency spectrum value at a second peak point, and

(c) a ratio of the first and second value as a representation of blood pressure variation; and

comparing said ratio with a threshold value to provide a comparison indicator; and

in response to said comparison indicator indicating said ratio exceeds the threshold value, generating an alert message associated with the threshold.