Detection of cardiac arrhythmia using mathematical representation of standard ΔRR probability density histograms

• US 7,146,206 B2
• Filed: 03/06/2003
• Issued: 12/05/2006
• Est. Priority Date: 03/20/2002
• Status: Active Grant

• Current Assignee: McGill University, Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Tateno, Katsumi, Glass, Leon
• Primary Examiner(s): Pezzuto, Robert E.
• Assistant Examiner(s): Gedeon, Brian T.
• Application Number:
  US10/382,385
• Publication Number:
  US 20050004486A1
• Time in Patent Office: 1,370 Days
• Field of Search: 600/521, 600/515, 600/516, 600/517, 600/518, 600/519
• US Class Current: 600/521
• CPC Class Codes: A61B 5/02405 Determining heart rate variability
• CPC Class Codes: A61B 5/361 Detecting fibrillation

Abstract

A method and a system for detecting cardiac arrhythmias that includes detecting RR intervals of the patient wherein each RR interval is an interval between two heart beats, and simulating standard probability density histograms of ΔRRs by means of a suitable probability distribution calculated through at least one mathematical formulae, wherein ΔRR is a difference between two successive RR intervals. Test probability density histograms of ΔRRs of the patient are constructed from the detected RR intervals. Finally, the standard and test histograms are compared to detect whether the patient suffers from cardiac arrhythmia. As non limiting examples, the standard probability density histograms of ΔRRs are modeled by a mathematical equation selected from the group consisting of: the Lorentzian distribution, the Gaussian distribution, the Student'"'"'s t-distribution, and a probability distribution including a linear combination of the Lorentzian and Gaussian distribution.

Claims

1. A method for detecting cardiac arrhythmia of a patient, comprising:

detecting RR intervals of the patient wherein each RR interval is an interval between two heart beats;

constructing standard probability density histograms of Δ

RRs collected during cardiac arrhythmia of a plurality of subjects, wherein Δ

RR is a difference between two successive RR intervals;

modeling the standard probability density histograms of Δ

RRs by means of a suitable probability distribution calculated through at least one mathematical formulae;

constructing test probability density histograms of Δ

RRs of the patient from the detected RR intervals of said patient; and

comparing the standard modeled histograms and the test histograms to detect whether the patient suffers from cardiac arrhythmia,

wherein comparing the standard modeled histograms and the test histograms to detect whether the patient suffers from cardiac arrhythmia comprises performing a Kolmogorov-Smirnov test, said method further comprising eliminating premature ventricular contractions prior to performing the Kolmogorov-Smirnov test.

2. A computer readable medium for encoding instructions for detecting cardiac arrhythmia of a patient, comprising:

instructions encoded on a computer readable medium for detecting RR intervals of a patient wherein each RR interval is an interval between two heart beats;

instructions encoded on the computer readable medium for constructing standard probability density histograms of Δ

RRs collected during cardiac arrhythmia of a plurality of subjects, wherein Δ

RR is a difference between two successive RR intervals;

instructions encoded on the computer readable medium for modeling the standard probability density histograms of Δ

RRs by means of a suitable probability distribution calculated through at least one mathematical formulae;

instructions encoded on the computer readable medium for constructing test probability density histograms of Δ

RRs of the patient from the detected RR intervals of said patient; and

instructions encoded on the computer readable medium for comparing the standard modeled histograms and the test histograms to detect whether the patient suffers from cardiac arrhythmia,

wherein the instructions encoded on the computer readable medium for comparing the standard modeled histograms and the test histograms to detect whether the patient suffers from cardiac arrhythmia comprises instructions for executing a Kolmogorov-Smirnov test, and executing instructions for eliminating premature ventricular contractions prior to performing the Kolmogorov-Smirnov test.

3. An apparatus for detecting cardiac arrhythmia of a patient, comprising:

means for detecting RR intervals of a patient wherein each RR interval is an interval between two heart beats;

means for constructing standard probability density histograms of Δ

RRs collected during cardiac arrhythmia of a plurality of subjects, wherein Δ

RR is a difference between two successive RR intervals;

means for modeling the standard probability density histograms of Δ

RRs by means of a suitable probability distribution calculated through at least one mathematical formulae;

means for constructing test probability density histograms of Δ

RRs of the patient from the detected RR intervals of said patient; and

means for comparing the standard modeled histograms and the test histograms to detect whether the patient suffers from cardiac arrhythmia,

wherein comparing the standard modeled histograms and the test histograms to detect whether the patient suffers from cardiac arrhythmia comprises performing a Kolmogorov-Smirnov test,

and wherein said apparatus also includes means for eliminating premature ventricular contractions prior to performing the Kolmogorov-Smirnov test.