Name
Abstract | ||
|---|---|---|
<italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Background:</i>
T-wave (TW) morphology indices based on time-warping (
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) have shown significant cardiovascular risk stratification value. However, errors in the location of TW boundaries may impact their prognostic power. Our aim was to test the hypothesis that a weighted time-warping function (WF) would reduce the sensitivity of
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to these errors and improve their clinical significance.
<italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Methods:</i>
The WFs were proportional to (i) the reference TW (
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), and (ii) the absolute value of its derivative (
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). The index
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was recalculated using these WFs, and its performance was compared to the unweighted control case (
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) in four different scenarios: 1) robustness against simulated TW boundaries location errors; 2) ability to retain physiological information in an electrophysiological cardiac model; 3) ability to monitor blood potassium concentration changes (
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) in 29 hemodialysis (HD) patients; 4) and the sudden cardiac death (SCD) risk stratification value of the TW morphology restitution (TMR) index, derived from
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, in 651 chronic heart failure (CHF) patients.
<italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Results and Discussion:</i>
The WFs led to a reduced sensitivity (
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) of
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to TW boundary location errors as compared to
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(median
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=0.19 and 0.22 and 0.35 for
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,
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and
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, respectively). They also preserved the physiological relationship between
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and repolarization dispersion changes at ventricular level. No improvements in
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tracking were observed for the HD patients (Pearson’s median correlation [
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] between
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and
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was
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for
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,
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and
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). In CHF patients, the SCD risk stratification value of TMR was improved by applying
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(hazard ratio, HAR, of 2.80), followed by
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(HAR=2.32) and
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(HAR=2.23).
<italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Conclusions and Significance:</i>
The proposed WFs, with
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showing the best performance, increased the robustness of time-warping based markers against TW location errors preserving their physiological information content and boosting their SCD risk stratification value. Results from this work support the use of
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when deriving
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for future clinical applications. |
Year | DOI | Venue |
|---|---|---|
2022 | 10.1109/TBME.2022.3153791 | IEEE Transactions on Biomedical Engineering |
Keywords | DocType | Volume |
Arrhythmias, Cardiac,Biomarkers,Death, Sudden, Cardiac,Electrocardiography,Heart Failure,Heart Ventricles,Humans,Risk Factors | Journal | 69 |
Issue | ISSN | Citations |
9 | 0018-9294 | 0 |
PageRank | References | Authors |
0.34 | 6 | 7 |
Name | Order | Citations | PageRank |
|---|---|---|---|
| Flavio Palmieri | 1 | 0 | 0.34 |
| Pedro Gomis | 2 | 0 | 0.34 |
| Dina Ferreira | 3 | 0 | 0.34 |
| Esther Pueyo | 4 | 0 | 0.68 |
| Juan Pablo Martinez | 5 | 0 | 0.34 |
| Pablo Laguna | 6 | 394 | 63.39 |
| Julia Ramirez | 7 | 0 | 0.34 |