hmmm I can see why Genitruc thinks this seems bluffy..

The only hands that I think can flat call the turn are flush/nut flush/88/TT

But I dont think a set would flat call this flop so I dont think those hands are in his range.

So now we have flush and flush draw potentially flat calling turn. Given that I think these are the most likely hands after the turn call, I think check/call is the best line on the river, to catch a bluff from a bare A/K hearts.

I think if you call this you get shown a flush a high percentage of time. Would he push a flush on a paired board? If he wouldn't, then this could really be a bluff since I don't think we see a boat here due to the flat call on flop.