Entropy Measures in Analysis of Head up Tilt Test Outcome for Diagnosing Vasovagal Syncope
Abstract
:1. Introduction
2. Entropy Measures
2.1. Sample Entropy
2.2. Fuzzy Entropy
2.3. Shannon Entropy
2.4. Conditional Entropy
2.5. Permutation Entropy
3. Materials and Methods
3.1. Study Group
3.2. Head up Tilt Test
3.3. Data Analysis and Statistical Methods
4. Results
4.1. Comparisons of Entropies between HUTT Phases in the HUTT(+) and HUTT(−) Group
4.2. Comparisions of Entropies in the HUTT(+) versus HUTT(−) Group in Individual Phases of HUTT
5. Discussion
6. Conclusions
Author Contributions
Funding
Conflicts of Interest
References
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Baseline | HUTT(+) (n = 57: F = 43, M = 14) | HUTT(−) (n = 23: F = 17, M = 6) |
---|---|---|
Female-age (year) | 35.6 ± 16 | 32.3 ± 12 |
Male-age (year) | 41.7 ± 15.6 | 43 ± 15 |
HR (bpm) | 72.06 ± 9.98 | 70.46 ± 11.35 |
sBP (mmHg) | 108.6 ± 25.4 | 102.6 ± 20.4 |
dBP(mmHg) | 68.0 ± 19.7 | 66.1 ± 16.8 |
Hypertension | 3 | 0 |
Diabetes | 0 | 0 |
Medication | 2 | 4 |
Entropy | Embedding Dimension (m) | Threshold (r) | Time Delay () |
---|---|---|---|
SE | 2 | 1 | |
FE | 2 | 1 | |
ShE | 2 | - | 1 |
CE 1 | 2 | - | 1 |
PE | 3 | - | 1 |
Parameter | Phase I (supine) | Phase IIa (tilt) | Phase III (pre-syncope) |
---|---|---|---|
Sample Entropy [29] | |||
SE (RRI) | 1.35 ± 0.30 | 0.88 ± 0.30 | 0.34 ± 0.20 |
SE (sBP) | 0.88 ± 0.44 | 0.82 ± 0.30 | 0.51 ± 0.30 |
SE (dBP) | 0.91 ± 0.42 | 0.76 ± 0.31 | 0.41 ± 0.30 |
SE (SV) | 1.16 ± 0.32 | 0.83 ± 0.30 | 0.95 ± 0.40 |
Fuzzy Entropy | |||
FE (RRI) | 0.037 ± 0.017 | 0.027 ± 0.017 | 0.008 ± 0.01 |
FE (sBP) | 0.18 ± 0.12 | 0.13 ± 0.083 | 0.05 ± 0.046 |
FE (dBP) | 0.22 ± 0.13 | 0.14 ± 0.096 | 0.05 ± 0.06 |
FE (SV) | 0.30 ± 0.18 | 0.19 ± 0.13 | 0.26 ± 0.17 |
Shannon Entropy | |||
Sh (RRI) | 2.52 ± 0.30 | 2.22 ± 0.25 | 1.59 ± 0.56 |
Sh (sBP) | 2.23 ± 0.41 | 2.20 ± 0.23 | 2.02 ± 0.25 |
Sh (dBP) | 2.27 ± 0.42 | 2.16 ± 0.23 | 1.93 ± 0.27 |
Sh (SV) | 2.37 ± 0.21 | 1.91 ± 0.43 | 2.17 ± 0.32 |
Conditional Entropy | |||
CE (RRI) | 1.05 ± 0.22 | 0.76 ± 0.18 | 0.43 ± 0.26 |
CE (sBP) | 0.75 ± 0.25 | 0.70 ± 0.20 | 0.52 ± 0.18 |
CE (dBP) | 0.78 ± 0.26 | 0.66 ± 0.18 | 0.45 ± 0.19 |
CE (SV) | 0.88 ± 0.15 | 0.64 ± 0.20 | 0.76 ± 0.20 |
Permutation Entropy | |||
PE (RRI) | 2.46 ± 0.15 | 2.40 ± 0.16 | 2.49 ± 0.15 |
PE (sBP) | 2.41 ± 0.28 | 2.32 ± 0.14 | 2.36 ± 0.14 |
PE (dBP) | 2.43 ± 0.28 | 2.30 ± 0.17 | 2.36 ± 0.15 |
PE (SV) | 2.45 ± 0.08 | 2.4 ± 0.09 | 2.43 ± 0.09 |
Parameter | Phase I (supine) | Phase IIa (tilt) | Phase IIb (ntg) | Phase III (pre-syncope) |
---|---|---|---|---|
Sample Entropy [29] | ||||
SE (RRI) | 1.50 ± 0.30 | 1.0 ± 0.3 | 0.34 ± 20 | 0.38 ± 0.24 |
SE (sBP) | 1.0 ± 0.50 | 0.84 ± 0.36 | 0.81 ± 0.25 | 0.80 ± 0.30 |
SE (dBP) | 1.01 ± 0.50 | 0.86 ± 0.36 | 0.82 ± 0.26 | 0.60 ± 0.30 |
SE (SV) | 1.06 ± 0.30 | 0.84 ± 0.30 | 0.92 ± 0.30 | 1.08 ± 0.30 |
Fuzzy Entropy | ||||
FE (RRI) | 0.037 ± 0.017 | 0.026 ± 0.013 | 0.014 ± 0.012 | 0.034 ± 0.046 |
FE (sBP) | 0.25 ± 0.20 | 0.17 ± 0.10 | 0.10 ± 0.05 | 0.10 ± 0.06 |
FE (dBP) | 0.26 ± 0.20 | 0.19 ± 0.12 | 0.16 ± 0.85 | 0.10 ± 0.07 |
FE (SV) | 0.27 ± 0.15 | 0.18 ± 0.10 | 0.26 ± 0.15 | 0.44 ± 0.29 |
Shannon Entropy | ||||
Sh (RRI) | 2.56 ± 0.23 | 2.23 ± 0.35 | 2.05 ± 0.25 | 1.88 ± 0.36 |
Sh (sBP) | 2.30 ± 0.42 | 2.24 ± 0.25 | 2.24 ± 0.22 | 2.16 ± 0.22 |
Sh (dBP) | 2.27 ± 0.39 | 2.24 ± 0.25 | 2.24 ± 0.22 | 2.07 ± 0.29 |
Sh (SV) | 2.32 ± 0.28 | 1.92 ± 0.28 | 2.32 ± 0.18 | 2.38 ± 0.24 |
Conditional Entropy | ||||
CE (RRI) | 0.46 ± 0.13 | 0.80 ± 0.19 | 0.51 ± 0.15 | 0.48 ± 0.20 |
CE (sBP) | 0.79 ± 0.29 | 0.74 ± 0.17 | 0.70 ± 0.15 | 0.65 ± 0.14 |
CE (dBP) | 0.77 ± 0.27 | 0.72 ± 0.19 | 0.69 ± 0.17 | 0.56 ± 0.17 |
CE (SV) | 0.85 ± 0.17 | 0.63 ± 0.21 | 0.77 ± 0.15 | 0.85 ± 0.17 |
Permutation Entropy | ||||
PE (RRI) | 2.47 ± 0.09 | 2.37 ± 0.18 | 2.43 ± 0.24 | 2.70 ± 0.32 |
PE (sBP) | 2.37 ± 0.18 | 2.36 ± 0.15 | 2.25 ± 0.13 | 2.32 ± 0.13 |
PE (dBP) | 2.44 ± 0.17 | 2.37 ± 0.18 | 2.27 ± 0.16 | 2.35 ± 0.13 |
PE (SV) | 2.46 ± 0.05 | 2.41 ± 0.08 | 2.35 ± 0.11 | 2.40 ± 0.11 |
Parameter | HUTT(−) vs. HUTT(+) | |||||
---|---|---|---|---|---|---|
Phase I (supine) | p | Phase IIa (tilt) | p | Phase III (pre-syncope) | p | |
Sample Entropy [21] | ||||||
SE (RRI) | 0.46 | 0.48 | 0.52 | |||
SE (sBP) | 0.43 | 0.99 | 0.0006 | |||
SE (dBP) | 0.35 | 0.15 | 0.0001 | |||
SE (SV) | 0.13 | 0.73 | 0.24 | |||
Fuzzy Entropy | ||||||
FE (RRI) | 0.98 | 0.85 | 0.000007 | |||
FE (sBP) | 0.30 | 0.14 | 0.00004 | |||
FE (dBP) | 0.49 | 0.13 | 0.0007 | |||
FE (SV) | 0.40 | 0.71 | 0.007 | |||
Shannon Entropy | ||||||
Sh (RRI) | 0.50 | 0.57 | 0.07 | |||
Sh (sBP) | 0.23 | 0.48 | 0.01 | |||
Sh (dBP) | 0.88 | 0.24 | 0.055 | |||
Sh (SV) | 0.52 | 0.86 | 0.01 | |||
Conditional Entropy | ||||||
CE (RRI) | 0.00001 | 0.36 | 0.33 | |||
CE (sBP) | 0.26 | 0.29 | 0.003 | |||
CE (dBP) | 0.89 | 0.11 | 0.012 | |||
CE (SV) | 0.36 | 0.92 | 0.09 | |||
Permutation Entropy | ||||||
PE (RRI) | 0.88 | 0.32 | 0.002 | |||
PE (sBP) | 0.12 | 0.27 | 0.18 | |||
PE (dBP) | 0.46 | 0.26 | 0.57 | |||
PE (SV) | 0.81 | 0.58 | 0.22 |
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Buszko, K.; Piątkowska, A.; Koźluk, E.; Fabiszak, T.; Opolski, G. Entropy Measures in Analysis of Head up Tilt Test Outcome for Diagnosing Vasovagal Syncope. Entropy 2018, 20, 976. https://doi.org/10.3390/e20120976
Buszko K, Piątkowska A, Koźluk E, Fabiszak T, Opolski G. Entropy Measures in Analysis of Head up Tilt Test Outcome for Diagnosing Vasovagal Syncope. Entropy. 2018; 20(12):976. https://doi.org/10.3390/e20120976
Chicago/Turabian StyleBuszko, Katarzyna, Agnieszka Piątkowska, Edward Koźluk, Tomasz Fabiszak, and Grzegorz Opolski. 2018. "Entropy Measures in Analysis of Head up Tilt Test Outcome for Diagnosing Vasovagal Syncope" Entropy 20, no. 12: 976. https://doi.org/10.3390/e20120976
APA StyleBuszko, K., Piątkowska, A., Koźluk, E., Fabiszak, T., & Opolski, G. (2018). Entropy Measures in Analysis of Head up Tilt Test Outcome for Diagnosing Vasovagal Syncope. Entropy, 20(12), 976. https://doi.org/10.3390/e20120976