Heart attack in it's current form of increasing the chances of hearts dropping on a kill doesn't seem to have much effect. It is hard to tell if it is work,and even if it is it doesn't help as much. So i propose two suggestions:

-Make hearts dropped by the ability look artistically different
As proposed in this thread, the objective would be to alter the appearance of the hearts that are specifically dropped from this skill so that players can know when the skill is working.

-Make Heart Attack heal directly
Once a monster enchanted with Heart Attack will heal all players directly the moment it dies. This will not always heal, and the chances of healing would be the same as the chances of a heart dropping, as well as the health recovered would be the same as the size of the heart dropped. This way, Heart attack would have a more profound effect on the outcome of battle while not making the skill too over powered. Defense orbs dropped from Iron Heart Attack must still be picked up individually.

Discussions and revisions are accepted and encouraged.