Goal: Learn the basics of the ECG signal analysis

• Chapter 8 on Cardiovascular Psychophysiology in: John T. Cacioppo, Louis G. Tassinary, Gary G. Berntson - Handbook of Psychophysiology (Cambridge University Press, 2007). The most important parts:
  • Anatomy and physiology: Overview, The heart, The cardiac cycle (pp. 182-183; figures on p. 184)
  • Psychophysiological measures: ECG, Heart rate, Heart rate variability (pp. 193-197)
    • Note: we are using the 3 channel ECG with RA/LA/LL (right arm/left arm/left leg) electrodes able to catch I/II/III bipolar leads, so there is no need to remember the placement of other electrodes (V1-V6) and leads (aVL, aVR, aVF)
  • Psychophysiological context (pp. 204-205)
• Pan–Tompkins algorithm (the most common algorithm for QRS complex detection)

1. Q&A Session:
   1. Can you identify the QRS complex in the ECG signal?
   2. In which locations are electrodes placed for 3-channel ECG?
   3. What extremity leads (PL: odprowadzenia kończynowe) do we measure with 3-channel ECG?
   4. What is the difference between ECG and PPG? How is PPG measured?
   5. What is the HRV analysis?
   6. What is the Pan-Tompkins algorithm used for?
2. Measurement time:
   1. The electrode placement for ECG measurement is based on Einthoven's triangle, composed of three leads (I, II, III). Measurement of all three at once is possible in a clinical setup with 12 electrodes. We have only 3 electrodes, which allows us to measure one selected lead at a time. But: each lead is based on the same positions of the electrodes - so you just need to stick them once and then rearrange the wires
   2. Electrode placement:
      • RA (right arm) > in the dimple below the sternum; on the “soft piece of flesh” (not on muscles or bones)
      • LA (left arm) > in the same way as RA, but on the left side
      • LF (left foot) > under the last left rib, on the soft part of the body
   3. Follow the Devices 101 lab to connect the biosignalsplux with the PC
   4. Use the ECG Datasheet and ECG User Manual to properly record the ECG signal
   5. Tasks:
      1. Check all three leads (I, II, III) from Einthoven's triangle (for details, see page 7 in ECG User Manual)
      2. What happens when the + (red) and - (black) electrodes are swapped? Check it out!
   6. At the end of class:
      1. clean the equipment with disinfectant wipes
      2. throw away the disposable electrodes (or keep them as souvenirs )
      3. pack all items in bags
      4. make sure all items are in the case:
         • biosignalsplux hub
         • bluetooth dongle
         • 4 sensors (each has a sticker with the name on it)
         • reference electrode (single, no stickers)
         • power supply
      5. give the case to the teacher
3. Practice session:
   1. Today's lab is placed in one Jupyter Notebook: Electrocardiography (ECG)
4. Advanced practice session:
   1. If you want to tackle additional topics, do the optional Advanced section in the notebook. It will give you the opportunity to explore basics of the HRV analysis.

• Chapter 8 on Cardiovascular Psychophysiology in: John T. Cacioppo, Louis G. Tassinary, Gary G. Berntson - Handbook of Psychophysiology (Cambridge University Press, 2016) – great handbook if you want to know more about all the physiology behind analysed signals (3rd edition available online via EBSCO)
• You can also check Dzedzickis et al. - Human Emotion Recognition: Review of Sensors and Methods (Sensors, 2020) for a short summary of ECG measurement
• ECGpedia (a free electrocardiography tutorial and textbook to which anyone can contribute, designed for medical professionals such as cardiac care nurses and physicians)
  • You can start here: ECG Basics
• FibriCheck Beat-to-Beat Accuracy Compared With Wearable ECG in Broad Dynamic Range (ECG and PPG compared)
• ECG Facts Made Incredibly Quick! (provides instant access to information that every nurse needs for safe patient care; you can download it from Academia.edu)

• hrv-analysis (HRV analysis based on R-R intervals)
• HeartPy (HR analysis for PPG signal; not for ECG)

• NeuroKit2 (toolbox for BVP, ECG, EDA, EEG, EMG, EOG, Respiration; it has a physiological signal generator)
• BioSPPy (toolbox for BVP, ECG, EDA, EEG, EMG, Respiration)