oh i don't have the perfect answer for you but they are skilled and do this job daily so as my 2nd ohs my heart lay in middle of my chest due to scar tissue and they were aware and able to do it without cutting my heart or cutting it in half
If your relating to equipment in your question they use a a saw.
if your worried or scared don't be cus this is their practice and Dr's are very skilled not to cut into your internal organs.
Hope this helped you some in answering from my experience.
I found a page with the instruments used. The brest bone saw looks like a mini saw zaw but has a devise on the end that looks like it would fit under the bone and limit the depth of the cut.
Bugchucker I don't think I want to watch them either. Mabe after its over.
Yiee. Sternum Saw! I'm glad this question was asked, because I always wondered about it too. I pictured a big chainsaw, even though I know that is ridiculous.
I think it's funny explaining it to non-heart-issue people. The looks on their faces...we might as well be Supermans and Superwomans, all of us.
Matter of fact...I think we are