Some heart mechanical reworks

[MrMelbert]

You can no longer arbitrarily have a heart attack from high levels of pain/traumatic shock

Instead, having an excessively high blood pressure or heart rate causes heart damage every tick
Eventually, if the excessively high bp / bpm is maintained, there is a chance per tick your heart will stop

So, now when you are in high amounts of pain/traumatic shock, your heart rate is boosted up, causing heart damage and eventually cardiac arrest

Defibrillating someone with an excessively high heart rate will bring it back down to a more stable rhythm for a short period
This can be used to stave off heart damage or cardiac arrest from an excessively high pulse rate. Someone with Tachycardia will now indicate in the health analyzer that you can defibrillate to help abate the effects.

Blood loss no longer contributes directly to reduced consciousness, though it does still cap your consciousness at certain values depending on your blood level. Instead, blood loss will kill you through reduced blood pressure - if you fall below the lethal threshold your heart will stop.

When you check yourself for injuries, you can now feel your heart rate vaguely.
Checking your own pulse will probably come soon since I only just thought of it as of writing.