I know with pistol and rifle bullets and their small diameters, respectively, this is a pipe-dream. However, in Latvia is a company that makes shotgun slugs claiming to have done tests, etc. and determining that the heart is stopped at the second the projectile hits the animal due to the shock-wave. I know this sounds bogus as all get-out, but they have pictures of these animals showing them dead where they were hit and the entrance hole has all sorts of organs from gut to lung-tissue blown out of it by what must be pneumatic or hydraulic pressure.
Could it be that when something this large hits an organ it does cause some of this effect and with a solid hit may indeed have an impact on the circulatory system? The tests they have done seem to indicate so, but of course I am not going to say it is so just because a manufacturer says so.
Here is a link, be forwarned, it is slightly graphic in the manner I described above, so may not want to open it at work/whatever. The wording is a bit “odd” and sounds snake-oil esque, but it is clear that being based in Latvia, their English is not up to the level that an English-speaking company’s might be, so I think some slack should be cut as they may not understand hyperbole or these words may be different in their language and the translation may not have carried over. Just a thought as to why they would say “Massively enormous” when describing ballistics instead of using it like the rest of us would when drunk at a bar.
http://www.ddupleks.lv/EN/ddupleks_products/show/Rossa32
http://www.ddupleks.lv/EN/articles/show/product-design