Method and apparatus to optimally measure cardiac depolarization/repolarization instability
First Claim
1. A method for identifying and measuring electrocardiographic altemans from at least one electrocardiographic (ECG) signal representative of the electric activity of a heart of a patient, the method comprising the steps of:
- obtaining the ECG signal over a predetermined number of cardiac cycles of the patient'"'"'s heart;
dividing the ECG signal into its individual cardiac cycles, each cardiac cycle having a depolarization portion and a repolarization portion;
dividing the repolarization portion of each cardiac cycle into a plurality of repolarization segments;
separately measuring the amplitude of each of the plurality of repolarization segments contained in the repolarization portion during each cardiac cycle, the amplitude of each repolarization segment for each cardiac cycle being measured from a repolarization reference baseline drawn between a first base segment occurring immediately prior to the repolarization portion of the present cardiac cycle and a second base segment occurring immediately prior to the depolarization portion of the subsequent cardiac cycle; and
digitally processing the amplitude measurements for the repolarization segments to determine the presence of alternans in the physiologic signals.
1 Assignment
0 Petitions
Accused Products
Abstract
A method of identifying and measuring altemans in an electrocardiographic (ECG) signal representative of the electric activity of a heart of a patient. The ECG signals from the patient are divided into individual cardiac cycles and the amplitude of four segments of the repolarization portion and the depolarization portion of each cardiac cycle are measured. The amplitude for each of the repolarization segments are measured from a reference baseline that is determined by a first base segment occurring immediately prior to the repolarization portion of the present cardiac cycle and a second base segment occurring immediately before the depolarization portion of the next cardiac cycle in the sequence. Based upon the amplitude measurements over the repolarization and the depolarization portions of each cardiac cycle, digital signal processing is applied to the measurements to generate eigenvariables. A spectral density is calculated for each of the eigenvariables, which spectral densities can be used to determine both the presence of altemans and the respiratory frequency.
15 Citations
16 Claims
-
1. A method for identifying and measuring electrocardiographic altemans from at least one electrocardiographic (ECG) signal representative of the electric activity of a heart of a patient, the method comprising the steps of:
-
obtaining the ECG signal over a predetermined number of cardiac cycles of the patient'"'"'s heart;
dividing the ECG signal into its individual cardiac cycles, each cardiac cycle having a depolarization portion and a repolarization portion;
dividing the repolarization portion of each cardiac cycle into a plurality of repolarization segments;
separately measuring the amplitude of each of the plurality of repolarization segments contained in the repolarization portion during each cardiac cycle, the amplitude of each repolarization segment for each cardiac cycle being measured from a repolarization reference baseline drawn between a first base segment occurring immediately prior to the repolarization portion of the present cardiac cycle and a second base segment occurring immediately prior to the depolarization portion of the subsequent cardiac cycle; and
digitally processing the amplitude measurements for the repolarization segments to determine the presence of alternans in the physiologic signals. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8)
-
-
9. A method for identifying and measuring electrocardiographic altemans from at least one electrocardiographic (ECG) signal representative of the electric activity of a heart of a patient, the method comprising the steps of:
-
obtaining the ECG signal over a predetermined number of cardiac cycles of a patient'"'"'s heart;
dividing the ECG signal into its individual cardiac cycles, each cardiac cycle having a depolarization portion and a repolarization portion;
dividing the repolarization portion of each cardiac cycle into a plurality of repolarization segments;
separately measuring the amplitude of the plurality of repolarization segments contained in the repolarization portion during each cardiac cycle, the amplitude of each repolarization segment being measured from a repolarization reference baseline calculated from the ECG signal for only the present cardiac cycle; and
digitally processing the amplitude measurements from the plurality of repolarization segments for each cardiac cycle to determine the presence of alternans in the physiologic signals. - View Dependent Claims (10, 11, 12, 13, 14, 15, 16)
-
Specification