PREDICTING ATRIAL FIBRILLATION OR STROKE USING P-WAVE ANALYSIS

1 . An electrocardiogram (ECG) monitoring system comprising:

a pair of electrodes electrically coupled to an ECG sensor and configured to receive ECG data from a patient;

a computer-readable memory; and

wherein the ECG sensor is configured to:

receive the ECG data from the pair of electrodes;

detect an onset and an offset of a first candidate P-wave represented in the ECG data;

calculate a quality score of the first candidate P-wave by calculating a quality score of ECG data between the onset and the offset of the first candidate P-wave;

detect an onset and an offset of a second candidate P-wave represented in the ECG data;

calculate a quality score of the second candidate P-wave by calculating a quality score of ECG data between the onset and the offset of the second candidate P-wave;

compare the quality score of the first candidate P-wave with the quality score of the second candidate P-wave;

in response to determining, based on the comparison, that the first candidate P-wave has a lower quality score than the second candidate P-wave, discard the first candidate P-wave;

store, in the computer-readable memory, an indication of the second candidate P-wave;

calculate a characteristic of the second candidate P-wave, wherein the characteristic is at least one of a rate of rise of the stored P-wave, an area under the curve of the stored P-wave, and a duration of the stored P-wave.

2 . The system of claim 1 , wherein calculating the quality score of the first candidate P-wave comprises determining an average root mean square amplitude of noise between the onset and the offset of the first candidate P-wave.

3 . The system of claim 1 , wherein calculating the quality score of the first candidate P-wave comprises determining whether the first candidate P-wave coincides with an arrhythmia event.

4 . The system of claim 2 , wherein the circuitry is configured to detect an onset of the first candidate P-wave using a Hilbert transform.

5 . The system of claim 4 , wherein the circuitry is further configured to graphically present the calculated characteristic of the stored P-wave on a display.

6 . The system of claim 5 , wherein the circuitry is further configured to calculate an atrial conduction velocity based on the calculated characteristic of the stored P-wave.

7 . The system of claim 6 , wherein the circuitry is further configured to calculate an indication of a likelihood of atrial fibrillation or stroke based on the characteristic of the stored P-wave.

8 . The system of claim 1 , wherein the circuitry is further configure to store in the computer-readable memory a plurality of P-waves.

9 . A system for filtering P-waves comprising:

processing circuitry configured to:

receive ECG data from an ECG monitoring device;

detect an onset and an offset of a candidate P-wave represented in the ECG data;

calculate a quality score of the candidate P-wave by calculating a quality score of ECG data between the onset and the offset of the candidate P-wave;

compare the quality score of the candidate P-wave with a quality score threshold;

if the quality score of the candidate P-wave is equal to or greater than the quality score threshold, store an indication of the candidate P-wave to computer-readable memory, and

calculate a characteristic of the stored P-wave, wherein the characteristic is at least one of a rate of rise of the stored P-wave, an area under the curve of the stored P-wave, and a duration of the stored P-wave.

10 . The system of claim 9 , wherein calculating the quality score of the candidate P-wave comprises determining whether the P-wave coincides with an arrhythmia event, and wherein the calculation of the quality score of the candidate P-wave is configured such that when the candidate P-wave does not coincide with an arrhythmia event, the calculated quality score of the candidate P-wave exceeds the quality score threshold.

11 . The system of claim 9 , wherein the quality score of the candidate P-wave is an indicator of whether the candidate P-wave includes an ECG artifact, and wherein the quality score of the candidate P-wave is equal to or greater than the quality score threshold when the P-wave does not include an ECG artifact.

12 . The system of claim 9 , wherein the quality score threshold is determined based on at least one of: an error in the rate of rise of the stored P-wave, the area under the curve of the stored P-wave, or the duration of the stored P-wave.

13 . The system of claim 10 , wherein the circuitry is further configured to graphically present the calculated characteristic of the stored P-wave in a display.

14 . The system of claim 13 , wherein the circuitry is further configured to calculate an indication of a likelihood of atrial fibrillation or stroke based on the characteristic of the stored P-wave.

15 . The system of claim 9 , wherein the circuitry is further configured to store a plurality of P-waves in computer-readable memory.

16 . A method for filtering P-waves comprising:

receiving ECG data from an ECG monitoring device;

detecting an onset and an offset of a first candidate P-wave represented in the ECG data;

calculating a quality score of the first candidate P-wave by calculating a quality score of ECG data between the onset and the offset of the first candidate P-wave;

comparing the quality score of the first candidate P-wave with a quality score threshold;

if the quality score of the candidate P-wave is equal to or greater than the quality score threshold, storing the candidate P-wave;

if the quality score of the candidate P-wave is less than the quality score threshold, discarding the candidate P-wave; and

calculating a characteristic of the stored P-wave, wherein the characteristic is at least one of a rate of rise of the stored P-wave, an area under the curve of the stored P-wave, and a duration of the stored P-wave.

17 . The method of claim 16 , further comprising:

detecting an onset and an offset of a second candidate P-wave represented in the ECG data;

calculating a quality score of the second candidate P-wave by calculating a quality score of ECG data between the onset and the offset of the second candidate P-wave; and

setting the quality score threshold equal to the quality score of the second candidate P-wave.

18 . The method claim 16 , further comprising graphically presenting the calculated characteristic of the stored P-wave.

19 . The method of claim 18 , further comprising estimating an atrial conduction velocity based on the calculated characteristic of the stored P-wave.

20 . The method of claim 16 , further comprising estimating an indication of a likelihood of atrial fibrillation or stroke based on the characteristic of the stored P-wave.