TCP Keepalive is a much better solution for this problem.

Nearly all bitcoin pools utilize TCP keepalive to maintain connections with miners.

These are systems in which performance and DoS resistance are paramount.

My understanding, from the heartbleed page, is that the packets for the heartbeat have a specific packet type identifier and that you can use this to train an IDS to watch for the heartbleed attack.

I would guess that makes them identifiable?