There are 4 main problems in detecting the QRS complex in ECG traces:
Artefacts due to electrode motion
There are 4 main problems in detecting the QRS complex in ECG traces:
- Artefacts due to electrode motion
- Baseline wander (mostly caused by breathing and torso movements)
- Muscle artefact (broadband)
- T-waves with high-amplitude content.
The solution to these problems is to use a bandpass filter to remove:
Low-frequency changes such as baseline wander
High-frequency changes e.g. movement/muscle artefact
Most of the frequencies in the QRS complex are around 5-20 Hz
Once the “non-QRS” sections of the ECG have been attenuated, the QRS complex can be detected with a threshold detector.
