Mrs. B and I have made jerky a couple of times from beef heart. When we split up a critter, we ask for the heart, tongue and liver. The liver gets baked into dog treats, the tongue boiled for sandwich meat and the heart is sliced, seasoned and dried.
We made a marinade of tomato sauce, onion, soy sauce, salt, pepper, sesame oil and such. The heart was sliced with an electric knife - they kick ass! - and marinated for 24+ hours before drying. We have to do it in the summer, since the dehydrator won't get hot enough in a cool garage. At 80f, though, it heats to around 150f. Just right.
The end result is yummy!
jb