Slope-range ECG-derived respiration¶
What it does¶
Slope-range ECG-derived respiration estimates a beat-to-beat respiratory modulation signal from derivative ECG morphology around detected R waves.
When to use it¶
Use it when a respiratory signal is unavailable but reliable R-wave timing and a derivative ECG are available. It provides a relative respiration surrogate, not a measurement in physical respiratory units.
Canonical ID: ecg.sloperange
Inputs¶
| Name | Meaning | Type | Unit | Requirements |
|---|---|---|---|---|
decg |
Sampled derivative ECG signal. | real vector | a.u. | minimum length: 2; no NaN; finite |
r_wave_times |
R-wave occurrence times aligned with the derivative ECG. | real vector | s | minimum length: 1; no NaN; finite |
sampling_frequency |
Sampling frequency of the derivative ECG. | real scalar | Hz | greater than: 0; no NaN; finite |
Outputs¶
| Name | Meaning | Type | Unit |
|---|---|---|---|
edr |
Beat-to-beat ECG-derived respiration amplitude series. | real vector | a.u. |
upslopes |
Signal-aligned local upslope traces used for inspection. | real vector | a.u. |
downslopes |
Signal-aligned local downslope traces used for inspection. | real vector | a.u. |
upslope_max_positions |
Selected maximum-upslope position for each processed beat. | real vector | sample |
downslope_min_positions |
Selected minimum-downslope position for each processed beat. | real vector | sample |
How it works¶
For each R wave, the method compares the strongest local upslope with the strongest local downslope. Their difference forms the EDR amplitude. Signal-aligned slope traces and selected extrema positions are returned for visual inspection.
Interpretation and limitations¶
Interpret trends rather than absolute amplitudes. Incorrect R-wave detections, unstable QRS morphology, noise, or incomplete boundary windows can make the surrogate unreliable.
References¶
- Stylianos Kontaxis et al. (2020). ECG-derived Respiratory Rate in Atrial Fibrillation. IEEE Transactions on Biomedical Engineering. doi:10.1109/TBME.2019.2923587
- Carolina Varon et al. (2020). A Comparative Study of ECG-derived Respiration in Ambulatory Monitoring using the Single-lead ECG. Scientific Reports. doi:10.1038/s41598-020-62624-5