Homemade Continuous EKG

I have POTS, so it’s really important that I am able to monitor my heart rate closely. When I stand up, my heart rate can increase so rapidly that it can cause me to pass out and risk injury. In order to know it is rising too rapidly, I need to be alerted within 1-3s. Traditional smart watches are comfortable, but take 5-10s. Chest strap monitors are fast and accurate, but are only meant to be worn during a workout for about an hour and thus are not comfortable to wear all the time. Inspired by a Continuous EKG, this monitor allows for quick and accurate BPM alerts, whilst being comfortable to wear for a prolonged period of time.

The supplies used are:

1. 1 Polar H10 heart rate monitor
2. https://a.co/d/02i6siBh
3. 2 Mini conductive springs (0.6x6x10mm)
4. https://a.co/d/01NSf8XK
5. 2 3M red dot electrodes
6. https://a.co/d/01ngag9Y
7. Silver conductive glue
8. https://a.co/d/0cC8tU7T
9. 1 Waterproof Dexcom G6 adhesive patch
10. https://a.co/d/0aB1dxMu

Remove the monitor from the box and connect it to the chest strap momentarily. Download the Polar Flow app on your phone and create an account. Put on the chest strap and connect it via Bluetooth to the app (it needs to be on and working in order to connect). Connect the monitor to your smart watch via Bluetooth; the watch will then prioritize the data from the monitor over itself. Open the regular heart rate app on the watch, set any alerts necessary, and monitor your heart rate in real time. Take off the chest strap and remove the monitor from the strap.

Place the silver conductive glue on the base of each snap on the monitor. Place the springs over the snaps into the glue. Allow it to dry for 10 hours before using.

Place the electrodes in the same position as a continuous EKG, otherwise known as a Modified Lead II Configuration. Remove the backing from the first electrode and place it underneath your left clavicle. Mark the location for the second electrode by: aligning the first spring on the monitor with the first electrode, positioning the monitor at a 45 degree angle downward to the left, lightly pressing into the skin, and using the indentation from the second spring as a guide.

Remove the backing from the sticky side of the adhesive patch. Position the monitor with the logo facing upright and away from you, then press it into the center of the adhesive patch. Pick it up from the back side of the patch, align the springs with the electrodes, and stick the patch onto the surrounding skin. You can now remove the covering on the other side of the patch and ensure the electrodes are sealed under it as well. Congratulations, you're done!

If over patch is properly secured, it should keep the whole unit waterproof and allow it to be worn for an extended period of time. The dexcom over patches have a wear time of 14 days, but the 3M electrodes have a wear time of only 4 days; therefore the unit should not be worn for more than 4 days at a time. It is important to let the skin breathe in between for a full 12-24 hours to avoid Adhesive Medical Device-Related Skin Injury (MARSI), so you can shift the placement by 1-2 cm or just go without for a while. Polar rates the H10 for 400 hours of operation (~14 days), and it uses a CR 2025 3V lithium coin cell battery when it needs to be replaced.