Great job. I am still waiting for my arrow to dissapear where I am looking.
As for the heartshot being the reason for the lack of blood trail, that is doubtful. I've had deer with heart shots with very little blood, such as yours, and I've had deer shot with a 12 gauge slug that cut the heart into 2 pieces making it look like lasangua and the blood trail was incredible for the 60 yards it ran. It sounds like the holes in the chest just didn't open enough to let the blood leak out very well.
Anyway, great shot great recovery!