The first time I made my old style of heart I was pretty happy with the result. I think the heart was the 2nd or 3rd Body Part I tried to make and the image I worked off was an easier one.
Hearts are one of those things where everyone seems to represent them differently and concentrate on different elements being important. Sometimes it the fat on the front you see first, sometimes its the valves, sometimes the whole heart is all about the veins and arteries feeding it.
I based my new heart design on a diagram that showed the veins and arteries, the chambers and to a lesser extent the valves (they are just kinda hinted at if you know where to look. This New Heart has only been twice and the first two are gifts for a cardiologist and heart surgeon. I hope they love them!