I agree heartily with dick cress in that the easier shot is the double lung shot and is just as deadly. When I was 12 I shot my first deer with a 38 # draw weight. It went through both lungs and the deer went 50-60 yds tops. The blood trail was incredible. Another hunter with me said he heard it go by his stand staggering every couple steps and hacking up huge amounts of blood and chunks of lung and he was set up about 40 yds away on another trail. Anyway, why shoot for a softball when you can shoot at a basketball? The lung kills just as well and there is a much greater margin of error. Below the heart there isn't much except the brisket, it is also fairly close to being protected by the shoulder blade. The lungs are much more unprotected and if you miss low you may catch the heart. Definitely the double lung. I think it is possible, but you have to be lucky and at the right angle to catch both lungs and the heart, so don't count on it.