Victoria’s show is designed to be sort of a video lab notebook, part educational, part experimental. YouTube already has some pretty great science shows (*cough*cough*) but I’m happy to welcome Victoria to the fold. And Iggy too, I guess.
In this episode, in addition to meeting the main characters and hearing some inspiring words about the importance of failure in the scientific method, we learn a bit about cardiac electrophysiology, those nerve impulses that control our heartbeat.
I find that GIF hypnotic. The human heart has its own pacemakers built in. One is known as the sinoatrial (SA) node, the other as the atrioventricular node (AV). These are the upper and lower red dots above, respectively.
Cardiac cells are interesting because they are sort of like nerves and muscle cells combined, they can do work, but they can also propagate electrical impulses (although we should be clear, they are definitely classified as muscle cells).
Cells of the SA node sort of “leak” charge at a constant rate, which makes them fire (or send an electrical impulse) at that same constant rate. The result is a nice rhythmic heartbeat, controlled by its own cells.
When a heartbeat is initiated by a stray impulse at the bottom (ventricular) region of the heart, that’s what is known as a premature ventricular contraction, or PVC. That’s what happens to Iggy in this episode.
Single, isolated PVCs are pretty harmless, and most of us probably get them from time to time without even noticing. Leave it to Iggy to kill himself by trying to fix a problem that doesn’t exist.
At least Victoria was there to shock him back to life! Wonder if she’ll do that again at some point…?