I know this sounds kind of simple and silly but you could pick up one of those wristband pulse/blood pressure moniters.

#1, you could keep track of what sort of things are causing the higher pulse rate, both physical exertion and stress, and avoid those activities as much as possible.

#2, maybe this would give you a warning when your pulse starts climbing and you could take a "time-out" and relax for a few minutes before the pulse rate climbs too high.

Just a thought! Good luck!