Unfortunately, this is a fine point of logic many people will miss.

If a person gets on a roller coaster and dies of a heart attack, it was the ride that killed them but it is not the coaster's fault because it is assumed that a typical adult human being could easily survive such an experience.

Similarly, specific police restraint techniques are chosen because they are effective but not typically lethal. And if you've got a heart condition and still choose to get on the ride, then that's on you.