This picture is in time with the average heart rate. What you’re hearing is the sound of your blood pumping, which you aren’t normally aware of. This picture tricks your mind into making yourself aware of your heart rate, so you hear it.
“Now all you can do is wait. It must be hard for you, but there is a right time for everything. Like the ebb and flow of tides. No one can do anything to change them. When it is time to wait, you must wait.”