The first logical error here is that you're assuming the deputies have life bios on all the prisoners. As if they knew that this guy was a coke head with heart problems, and that if he resists they can only use such-and-such restraint. In fact, the onus is clearly on the prisoner to know his own medical limitations and not put himself into a situation where his heart might core out.
As for the choke hold, it might surprise you that it is one of the safest techniques available for restraining actively resisting people (not just in a law enforcement context, but in any physical confrontation you might encounter on the street). A choke hold puts both the choker and chokee at less risk of injury. Going fist-to-fist with someone is actually a HORRIBLE way to fight, and often leads to broken bones, bleeding, fractures, and long-term injuries. Same thing when impact weapons become involved. A choke hold on the other hand, when executed properly, can end a fight quickly and with minimal potential for injury to everyone. Obviously this was not the case with this particular incident (and similar incidents), but that does not change the fact that the results were both unlikely and unintended. Surely you wouldn't prefer that the officers would have whipped out their batons and started clubbing him? Or just start throwing fists and elbows at the guy? Maybe a couple knees to the jugular? Are these methods more "compassionate" than a choke hold?
The video was extremely tame. There was no brutality there. No fight ever looks pretty. It's not a dance competition. Hell, even the Denver Post ultimately conceded that nothing was done wrong (which would be like Obama admitting that he's actually been a Republican this whole time).