Old World people who know about science, why does a human live through pulse, blood circulation etc, for 50 years without electricity input ?

The sinoatrial node in the right atrium of the heart is made of cells that produce electrical signals that cause the heart muscles to contract rhythmically.
It’s the heart’s pacemaker.

Essentially, the heart generates its own ‘electrical input’.

We dont.. Our own brain provides the chemical electic signals to the heart to beat. If it stops, so do we..😷