I always save the heart, even if it just goes into the grinder with the rest.
That extra lean ground beef that costs a bunch at the store? Beef hearts. Easy to trim off a wee bit of extra fat and the through the grinder it goes, otherwise they can hardly give them away.
Venison is pretty lean to begin with, and heart muscle is fairly tough, but too good to waste! I have used strip cut into leech shape as fish bait for walleye fishing too. Tough as old boots when raw.
Lungs, liver, etc., are the "Humbles". If you ever heard the expression "To be eating Humble Pie", that is what it was based upon. Not the most desired stuff, but it won't hurt anyone. I figure the crows and ravens gotta eat too. In Northern Alberta, they were often hanging around in the trees watching the whole show as we gutted, waiting on a hot meal, but I have seen a gut pile that I left out at night, completely cleaned up after it had frozen solid at 20 below. Pretty impressive clean up crew. All there was left was the gut contents, and a stain on the snow.
Some folks like the live, others not so much. I am in that latter category, don't usually carry Liver home unless I have a specific request for some. Always worth having a look at it for spots and lumps, to see if it looks generally healthy, other than the bullet holes anyways!
Cheers
Trev