Table 4 Pseudo code of the proposed methodology to find CV of ECG localized features.

From: Phase Space Reconstruction Based CVD Classifier Using Localized Features

1. Requirement: Find the CV distribution of all the localized features

2. E(t) = Healthy + Unhealthy ECG signal

3. Ef(t) = filtering(E(t))

4. Normalization: En(t) = (Ef(t) − Efmin(t))/(Efmax(t) − Efmin(t))

5. Extraction of boundaries:

    for i = 1 to length (En(t))

                         {E(1), E(2), E(3), —E(n),} = BD[En(t)]

    endfor

    where E(n) is the nth ECG beat.

6. Extracting ECG Features:

    for i = 1 to n

                         {PR[i], QRS[i], QT[i]} = FE[E(i)]

    endfor

7. Taking QT interval array for PSR analysis:

    QT(i), i {1, 2, 3, ....n}

8. Applying Sliding window on QT interval array:

    for z = 1 to n − 19

    SW(t) = {QT(z + 1), QT(z + 2), QT(z + 3)....QT(z + 19)}

    PSR_Image(k) = plot(SW(t), SW(t − 20))

    endfor

    SW = Sliding Window.

9. Box-count array:

    for x = 1 to k

    Box_count_array(x) = No. ofBlackBoxes(PSR_image(x))

    endfor

10. Sliding window on Box-count distribution:

       for m = 1 to x − 19

       CV(m) = CV(Box_count_array(m), Box_count_array(2), Box_count_array(3))...Box_count_array(m + 19)

       endfor

11. for i = 1 to m

       Thmax(i) = max[CV(i){1:a}]

       Thmin1(i) = min[CV(i){b:end}]

       endfor Note: pointa’ and ‘bin CV plot are corresponding toUnhealhty QT startandHealthy QT endwindows of Fig. 14

12. Thfinal_max_QT = max(Thmax(1), Thmax(2), Thmax(3)..Thmax(m))

       Thfinal_min_QT = min(Thmin(1), Thmin(2), Thmin(3)..Thmin(m))

13. Thfinal_min_QT and Thfinal_max_QT are the two thresholds of CV corresponing to QT interval, the similar procedure is followed for PR interval and QRS complex to find thresholds.