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  1. Article ; Online: pRR30, pRR3.25% and Asymmetrical Entropy Descriptors in Atrial Fibrillation Detection.

    Biczuk, Bartosz / Buś, Szymon / Żurek, Sebastian / Piskorski, Jarosław / Guzik, Przemysław

    Entropy (Basel, Switzerland)

    2024  Volume 26, Issue 4

    Abstract: Background: Early detection of atrial fibrillation (AF) is essential to prevent stroke and other cardiac and embolic complications. We compared the diagnostic properties for AF detection of the percentage of successive RR interval differences greater ... ...

    Abstract Background: Early detection of atrial fibrillation (AF) is essential to prevent stroke and other cardiac and embolic complications. We compared the diagnostic properties for AF detection of the percentage of successive RR interval differences greater than or equal to 30 ms or 3.25% of the previous RR interval (pRR30 and pRR3.25%, respectively), and asymmetric entropy descriptors of RR intervals. Previously, both pRR30 and pRR3.25% outperformed many other heart rate variability (HRV) parameters in distinguishing AF from sinus rhythm (SR) in 60 s electrocardiograms (ECGs).
    Methods: The 60 s segments with RR intervals were extracted from the publicly available Physionet Long-Term Atrial Fibrillation Database (84 recording, 24 h Holter ECG). There were 31,753 60 s segments of AF and 32,073 60 s segments of SR. The diagnostic properties of all parameters were analysed with receiver operator curve analysis, a confusion matrix and logistic regression. The best model with pRR30, pRR3.25% and total entropic features (H) had the largest area under the curve (AUC)-0.98 compared to 0.959 for pRR30-and 0.972 for pRR3.25%. However, the differences in AUC between pRR30 and pRR3.25% alone and the combined model were negligible from a practical point of view. Moreover, combining pRR30 and pRR3.25% with H significantly increased the number of false-negative cases by more than threefold.
    Conclusions: Asymmetric entropy has some potential in differentiating AF from SR in the 60 s RR interval time series, but the addition of these parameters does not seem to make a relevant difference compared to pRR30 and especially pRR3.25%.
    Language English
    Publishing date 2024-03-28
    Publishing country Switzerland
    Document type Journal Article
    ZDB-ID 2014734-X
    ISSN 1099-4300 ; 1099-4300
    ISSN (online) 1099-4300
    ISSN 1099-4300
    DOI 10.3390/e26040296
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article: Heart Rate Asymmetry, Its Compensation, and Heart Rate Variability in Healthy Adults during 48-h Holter ECG Recordings.

    Sibrecht, Greta / Piskorski, Jarosław / Krauze, Tomasz / Guzik, Przemysław

    Journal of clinical medicine

    2023  Volume 12, Issue 3

    Abstract: Heart rate asymmetry (HRA) reflects different contributions of heart rate (HR) decelerations and accelerations to heart rate variability (HRV). In this study, we examined various properties of HRA, including its compensation and HRV, in 48-h ... ...

    Abstract Heart rate asymmetry (HRA) reflects different contributions of heart rate (HR) decelerations and accelerations to heart rate variability (HRV). In this study, we examined various properties of HRA, including its compensation and HRV, in 48-h electrocardiogram (ECG) recordings in healthy adults. Furthermore, we compared sex differences in parameters used to quantify HRA and HRV. Variance-based and relative HRA and HRV parameters were computed for Holter ECG recordings lasting up to 48 h in 101 healthy volunteers. The median age of the subjects was 39 years, with 47 of them being men. The prevalence of all forms of HRA was statistically different from randomness (
    Language English
    Publishing date 2023-02-03
    Publishing country Switzerland
    Document type Journal Article
    ZDB-ID 2662592-1
    ISSN 2077-0383
    ISSN 2077-0383
    DOI 10.3390/jcm12031219
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article: Heart Rate Asymmetry in Healthy Children.

    Zalas, Dominika / Bobkowski, Waldemar / Piskorski, Jarosław / Guzik, Przemysław

    Journal of clinical medicine

    2023  Volume 12, Issue 3

    Abstract: Heart rate asymmetry (HRA) is a physiological phenomenon characterized by an unequal contribution of heart rate decelerations and accelerations to different heart rate variability (HRV) features. While HRA has been demonstrated in adults' ECGs of ... ...

    Abstract Heart rate asymmetry (HRA) is a physiological phenomenon characterized by an unequal contribution of heart rate decelerations and accelerations to different heart rate variability (HRV) features. While HRA has been demonstrated in adults' ECGs of different duration, a similar investigation in healthy children has not been conducted. This study investigated the variance- and number-based HRA features in 96 healthy children (50 girls and 46 boys, aged 3-18 years) using 24-h ECGs. Additionally, we studied sex differences in HRA. To quantify HRA, variance-based and relative contributions of heart rate decelerations to short-term (C1d), long-term (C2d), and total (CTd) HRV, and the number of all heartbeats (Nd) were computed. Heart rate decelerations contributed more to C1d, but less to C2d and CTd, and were less frequent than heart rate accelerations. Short-term HRA was better expressed in boys. The majority of children (93.7%) had short-term HRA, 88.5% had long-term HRA, 88.5% had total HRA, and 99.0% had more accelerations than decelerations. No sex differences were observed for the rate of various HRA features. Heart rate asymmetry is a common phenomenon in healthy children, as observed in 24-h ECGs. Our findings can be used as reference data for future clinical studies on HRA in children.
    Language English
    Publishing date 2023-02-02
    Publishing country Switzerland
    Document type Journal Article
    ZDB-ID 2662592-1
    ISSN 2077-0383
    ISSN 2077-0383
    DOI 10.3390/jcm12031194
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article: Asymmetric Properties of the Heart Rate Microstructure in Healthy Adults during 48 h ECG Recordings.

    Sibrecht, Greta / Piskorski, Jarosław / Krauze, Tomasz / Guzik, Przemysław

    Journal of clinical medicine

    2023  Volume 12, Issue 23

    Abstract: Heart rate asymmetry reflects the different contributions of heart rate (HR) decelerations and accelerations to heart rate variability (HRV). We examined the contribution of monotonic runs of HR accelerations and decelerations to the asymmetric ... ...

    Abstract Heart rate asymmetry reflects the different contributions of heart rate (HR) decelerations and accelerations to heart rate variability (HRV). We examined the contribution of monotonic runs of HR accelerations and decelerations to the asymmetric properties of the HR microstructure in the 48 h electrocardiograms (ECGs) of healthy adults (n = 101, 47 males, average age of 39 years) and analysed sex differences in the HR microstructure. The HR microstructure was asymmetric for runs of most lengths, except for sequences of two consecutive decelerations (DR2s) or accelerations (AR2s). Women had a higher prevalence of AR2s than men but fewer runs in the range of 4 to 11 consecutive accelerations (AR4-AR11s) and 5 to 11 consecutive decelerations (DR5-DR11s). The longest runs consisted of 47 consecutive accelerations (AR47s) and 27 consecutive decelerations (DR27s). More DR3s than AR3s and more DR4s than AR4s reveal a crossing of HR microstructure asymmetry. In conclusion, more acceleration than deceleration runs demonstrate that the HR microstructure was asymmetric in the 48 h ECGs. This phenomenon was present in both sexes but was more pronounced in men. For shorter runs of 3 and 4 consecutive heartbeats, there was a crossing of HR microstructure asymmetry, with more deceleration than acceleration runs.
    Language English
    Publishing date 2023-12-02
    Publishing country Switzerland
    Document type Journal Article
    ZDB-ID 2662592-1
    ISSN 2077-0383
    ISSN 2077-0383
    DOI 10.3390/jcm12237472
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article: A New Approach to Detecting Atrial Fibrillation Using Count Statistics of Relative Changes between Consecutive RR Intervals.

    Buś, Szymon / Jędrzejewski, Konrad / Guzik, Przemysław

    Journal of clinical medicine

    2023  Volume 12, Issue 2

    Abstract: Background: The ratio of the difference between neighboring RR intervals to the length of the preceding RR interval (x%) represents the relative change in the duration between two cardiac cycles. We investigated the diagnostic properties of the ... ...

    Abstract Background: The ratio of the difference between neighboring RR intervals to the length of the preceding RR interval (x%) represents the relative change in the duration between two cardiac cycles. We investigated the diagnostic properties of the percentage of relative RR interval differences equal to or greater than x% (pRRx%) with x% in a range between 0.25% and 25% for the distinction of atrial fibrillation (AF) from sinus rhythm (SR).
    Methods: We used 1-min ECG segments with RR intervals with either AF (32,141 segments) or SR (32,769 segments) from the publicly available Physionet Long-Term Atrial Fibrillation Database (LTAFDB). The properties of pRRx% for different x% were analyzed using the statistical procedures and metrics commonly used to characterize diagnostic methods.
    Results: The distributions of pRRx% for AF and SR differ significantly over the whole studied range of x% from 0.25% to 25%, with particularly outstanding diagnostic properties for the x% range of 1.5% to 6%. However, pRR3.25% outperformed other pRRx%. Firstly, it had one of the highest and closest to perfect areas under the curve (0.971). For pRR3.25%, the optimal threshold for distinction AF from SR was set at 75.32%. Then, the accuracy was 95.44%, sensitivity was 97.16%, specificity was 93.76%, the positive predictive value was 93.85%, the negative predictive value was 97.11%, and the diagnostic odds ratio was 514. The excellent diagnostic properties of pRR3.25% were confirmed in the publicly available MIT-BIH Atrial Fibrillation Database. In a direct comparison, pRR3.25% outperformed the diagnostic properties of pRR31 (the percentage of successive RR intervals differing by at least 31 ms), i.e., so far, the best single parameter differentiating AF from SR.
    Conclusions: A family of pRRx% parameters has excellent diagnostic properties for AF detection in a range of x% between 1.5% and 6%. However, pRR3.25% outperforms other pRRx% parameters and pRR31 (until now, probably the most robust single heart rate variability parameter for AF diagnosis). The exquisite pRRx% diagnostic properties for AF and its simple computation make it well-suited for AF detection in modern ECG technologies (mobile/wearable devices, biopatches) in long-term monitoring. The diagnostic properties of pRRx% deserve further exploration in other databases with AF.
    Language English
    Publishing date 2023-01-15
    Publishing country Switzerland
    Document type Journal Article
    ZDB-ID 2662592-1
    ISSN 2077-0383
    ISSN 2077-0383
    DOI 10.3390/jcm12020687
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article: Cerebral Perfusion Pressure-Guided Therapy in Patients with Subarachnoid Haemorrhage-A Retrospective Analysis.

    Gradys, Agata / Szrama, Jakub / Molnar, Zsolt / Guzik, Przemysław / Kusza, Krzysztof

    Life (Basel, Switzerland)

    2023  Volume 13, Issue 7

    Abstract: Background: Prevention and treatment of haemodynamic instability and increased intracranial pressure (ICP) in patients with subarachnoid haemorrhage (SAH) is vital. This study aimed to evaluate the effects of protocolised cerebral perfusion pressure ( ... ...

    Abstract Background: Prevention and treatment of haemodynamic instability and increased intracranial pressure (ICP) in patients with subarachnoid haemorrhage (SAH) is vital. This study aimed to evaluate the effects of protocolised cerebral perfusion pressure (CPP)-guided treatment on morbidity and functional outcome in patients admitted to the intensive care unit (ICU) with SAH.
    Methods: We performed a retrospective study comparing 37 patients who received standard haemodynamic treatment (control group) with 17 individuals (CPP-guided group) who were on the CPP-guided treatment aimed at maintaining CPP > 70 mmHg using both optimisations of ICP and mean arterial pressure (MAP).
    Results: MAP, cumulative crystalloid doses and fluid balance were similar in both groups. However, the incidence of delayed cerebral ischaemia was significantly lower in the CPP-guided group (14% vs. 64%,
    Conclusions: This preliminary analysis showed that implementing a CPP-guided treatment approach aimed at maintaining a CPP > 70 mmHg may reduce the occurrence of delayed cerebral ischaemia and improve functional outcomes in patients with SAH. This observation merits further prospective investigation of the use of CPP-guided treatment in patients with SAH.
    Language English
    Publishing date 2023-07-21
    Publishing country Switzerland
    Document type Journal Article
    ZDB-ID 2662250-6
    ISSN 2075-1729
    ISSN 2075-1729
    DOI 10.3390/life13071597
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article: Dependence of the Atrioventricular Conduction Time on the Conduction through the Atrioventricular Node and His-Purkinje System.

    Żuchowski, Bartosz / Błaszyk, Krzysztof / Piskorski, Jarosław / Wykrętowicz, Andrzej / Guzik, Przemysław

    Journal of clinical medicine

    2023  Volume 12, Issue 4

    Abstract: The electrical depolarization of the heart passes through various structures of the cardiac conduction system, which modify its conduction to different extents. In this study, we investigated the relationship between the atrioventricular conduction time ( ...

    Abstract The electrical depolarization of the heart passes through various structures of the cardiac conduction system, which modify its conduction to different extents. In this study, we investigated the relationship between the atrioventricular conduction time (AV interval) and its contributors, the atrioventricular node (AVN) and the His-Purkinje system (HPS), as represented by the AH and HV intervals, respectively. We also compared sex differences in these intervals and their relations. Resting intracardiac tracings lasting 5 min were obtained from 64 patients (33 women) during an invasive electrophysiological study. The aforementioned intervals were measured for all consecutive beats. The mean AH interval was 85.9 ms, HV 43.7 ms, and AV 129.6 ms. Men had longer AH (80.0 vs. 65.9 ms), HV (38.4 vs. 35.3 ms), and AV intervals (124.7 vs. 108.5 ms) than women. The AV intervals were linearly correlated with AH intervals in all patients (r
    Language English
    Publishing date 2023-02-07
    Publishing country Switzerland
    Document type Journal Article
    ZDB-ID 2662592-1
    ISSN 2077-0383
    ISSN 2077-0383
    DOI 10.3390/jcm12041330
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article: Statistical and Diagnostic Properties of pRRx Parameters in Atrial Fibrillation Detection.

    Buś, Szymon / Jędrzejewski, Konrad / Guzik, Przemysław

    Journal of clinical medicine

    2022  Volume 11, Issue 19

    Abstract: Background: We studied the diagnostic properties of the percentage of successive RR intervals differing by at least x ms (pRRx) as functions of the threshold value x in a range of 7 to 195 ms for the differentiation of atrial fibrillation (AF) from ... ...

    Abstract Background: We studied the diagnostic properties of the percentage of successive RR intervals differing by at least x ms (pRRx) as functions of the threshold value x in a range of 7 to 195 ms for the differentiation of atrial fibrillation (AF) from sinus rhythm (SR).
    Methods: RR intervals were measured in 60-s electrocardiogram (ECG) segments with either AF (32,141 segments) or SR (32,769 segments) from the publicly available Physionet Long-Term Atrial Fibrillation Database (LTAFDB). For validation, we have used ECGs from the Massachusetts Institute of Technology-Beth Israel Hospital (MIT-BIH) Atrial Fibrillation Database. The pRRx distributions in AF and SR in relation to x were studied by histograms, along with the mutual association by the nonparametric Spearman correlations for all pairs of pRRx, and separately for AF or SR. The optimal cutoff values for all pRRx were determined using the receiver operator curve characteristic. A nonparametric bootstrap with 5000 samples was used to calculate a 95% confidence interval for several classification metrics.
    Results: The distributions of pRRx for x in the 7-195 ms range are significantly different in AF than in SR. The sensitivity, specificity, accuracy, and diagnostic odds ratios differ for pRRx, with the highest values for x = 31 ms (pRR31) rather than x = 50 (pRR50), which is most commonly applied in studies on heart rate variability. For the optimal cutoff of pRR31 (68.79%), the sensitivity is 90.42%, specificity 95.37%, and the diagnostic odds ratio is 194.11. Validation with the ECGs from the MIT-BIH Atrial Fibrillation Database confirmed our findings.
    Conclusions: We demonstrate that the diagnostic properties of pRRx depend on x, and pRR31 outperforms pRR50, at least for ECGs of 60-s duration.
    Language English
    Publishing date 2022-09-27
    Publishing country Switzerland
    Document type Journal Article
    ZDB-ID 2662592-1
    ISSN 2077-0383
    ISSN 2077-0383
    DOI 10.3390/jcm11195702
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article: Using Minimum Redundancy Maximum Relevance Algorithm to Select Minimal Sets of Heart Rate Variability Parameters for Atrial Fibrillation Detection.

    Buś, Szymon / Jędrzejewski, Konrad / Guzik, Przemysław

    Journal of clinical medicine

    2022  Volume 11, Issue 14

    Abstract: Heart rate is quite regular during sinus (normal) rhythm (SR) originating from the sinus node. In contrast, heart rate is usually irregular during atrial fibrillation (AF). Complete atrioventricular block with an escape rhythm, ventricular pacing, or ... ...

    Abstract Heart rate is quite regular during sinus (normal) rhythm (SR) originating from the sinus node. In contrast, heart rate is usually irregular during atrial fibrillation (AF). Complete atrioventricular block with an escape rhythm, ventricular pacing, or ventricular tachycardia are the most common exceptions when heart rate may be regular in AF. Heart rate variability (HRV) is the variation in the duration of consecutive cardiac cycles (RR intervals). We investigated the utility of HRV parameters for automated detection of AF with machine learning (ML) classifiers. The minimum redundancy maximum relevance (MRMR) algorithm, one of the most effective algorithms for feature selection, helped select the HRV parameters (including five original), best suited for distinguishing AF from SR in a database of over 53,000 60 s separate electrocardiogram (ECG) segments cut from longer (up to 24 h) ECG recordings. HRV parameters entered the ML-based classifiers as features. Seven different, commonly used classifiers were trained with one to six HRV-based features with the highest scores resulting from the MRMR algorithm and tested using the 5-fold cross-validation and blindfold validation. The best ML classifier in the blindfold validation achieved an accuracy of 97.2% and diagnostic odds ratio of 1566. From all studied HRV features, the top three HRV parameters distinguishing AF from SR were: the percentage of successive RR intervals differing by at least 50 ms (pRR50), the ratio of standard deviations of points along and across the identity line of the Poincare plots, respectively (SD2/SD1), and coefficient of variation-standard deviation of RR intervals divided by their mean duration (CV). The proposed methodology and the presented results of the selection of HRV parameters have the potential to develop practical solutions and devices for automatic AF detection with minimal sets of simple HRV parameters. Using straightforward ML classifiers and the extremely small sets of simple HRV features, always with pRR50 included, the differentiation of AF from sinus rhythms in the 60 s ECGs is very effective.
    Language English
    Publishing date 2022-07-11
    Publishing country Switzerland
    Document type Journal Article
    ZDB-ID 2662592-1
    ISSN 2077-0383
    ISSN 2077-0383
    DOI 10.3390/jcm11144004
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article: Interrelationships between Peak Strain Dispersion, Myocardial Work Indices, Isovolumetric Relaxation and Systolic-Diastolic Coupling in Middle-Aged Healthy Subjects.

    Minczykowski, Andrzej / Guzik, Przemysław / Sajkowska, Anna / Pałasz-Borkowska, Anna / Wykrętowicz, Andrzej

    Journal of clinical medicine

    2023  Volume 12, Issue 17

    Abstract: In echocardiography, peak strain dispersion (PSD) is the standard deviation of the time to peak longitudinal strain for each left ventricular (LV) segment during systole. It assesses the coordination and synchrony of LV segment contractility. Global work ...

    Abstract In echocardiography, peak strain dispersion (PSD) is the standard deviation of the time to peak longitudinal strain for each left ventricular (LV) segment during systole. It assesses the coordination and synchrony of LV segment contractility. Global work efficiency (GWE) and global wasted work (GWW) quantify LV myocardial work and, if impaired, the coupling between LV systolic contraction and early relaxation. Isovolumetric relaxation (IVRT) measures the duration of initial LV relaxation, while the ratio of early diastolic recoil to systolic excursion (E'
    Language English
    Publishing date 2023-08-28
    Publishing country Switzerland
    Document type Journal Article
    ZDB-ID 2662592-1
    ISSN 2077-0383
    ISSN 2077-0383
    DOI 10.3390/jcm12175623
    Database MEDical Literature Analysis and Retrieval System OnLINE

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