Frequently asked questions (FAQ)

Welcome to the official support page for 'Heart Plot'.

How can I get in touch with you?

Please contact me via Email: dorfcode@icloud.com

Where do I find more information concerning the different patterns I might see in my plot?

You might find these studies interesting to discuss your pattern with your cardiologist:

Cardiac Arrhythmias Imprint Specific Signatures on Lorenz Plots
The clinical significance of Lorenz scatter plots in detecting ventricular parasystoles (PDF)
Dynamic Analysis of Heart Rate Variability through Motion Path Analysis of the Poincaré Plot (PDF)
Evaluation and Management of Premature Ventricular Complexes
Impact of catheter ablation for atrial fibrillation on cardiac ventricular electrical activity: assessment of premature ventricular complex burden

Is a Poincaré plot the same than a Lorenz plot?

Yes, a Poincaré plot and a Lorenz plot are the exact same thing.

What do the different colors in the heatmap tell me?

The heatmap shows a third dimension in the plot. Whenever the same RR/RR-pair (i.e. the same point in the plot) appears in a repetitive manner, it will change its colour each time, fading from yellow to purple. The fading color demonstrates how often a pair did appear.

What is the calculation for the Heart Rate Variability (HRV)?

The "Root Mean Square of Successive Differences (RMSSD)" is used. This is a standard metrics to get a view on Heart Rate Variability. Here is a study explaing all the differences.
An Overview of Heart Rate Variability Metrics and Norms

My Polar H10 (or heart rate sensor) is not connecting to the app.

Ensure that Bluetooth is enabled on your iPhone (Settings > Bluetooth).
Make sure you are actively wearing the chest strap and that the electrodes are slightly moistened for a good connection.
Important: Bluetooth heart rate monitors can usually only connect to one device or app at a time. Ensure your sensor is not currently connected to another app (like Apple Health or Polar Beat) or another device (like a smartwatch).
Make sure you have the latest firmware on the H10-device. You can update the firmware with the Polar Flow App.

Where is my exported CSV file saved?

When you tap the "Share" button, the app opens the standard iOS Share Sheet. From there, you can choose to save the file directly to your iPhone (via "Save to Files"), AirDrop it to your Mac, or email it to yourself for post-processing.

Does the app saves my heart rate data automatically?

To prioritize your privacy and save device storage, 'Heart Plot' streams the data live. If you want to keep a record of your RR intervals, you must manually export the CSV file at the end of a session and before closing the app. If you want to save the plot-view, you need to make a screenshot by yourself.
However, the app stores a copy on your iPhone for 7 days in your specific app-folder.

Can I use a sensor other than the Polar H10?

The app is optimized for the Polar H10. Other sensors have not been tested or verified.

Why do sometimes the RR-intervalls come in as a swell?

This is due to bluetooth package transport logic from the device to the iPhone. The app has no influence on this. Sometimes a package contains more than one value and the full content comes as a swell of values. However, the app does sort them in the correct order. In the plot and in the CSV-file the RR intervals are shown correctly.