I experienced the same thing during Induction, and even to a much lesser extent, still experience them now.

I suffered heart palpitations when I started low carbing. Not a faster beat, but a heavier and more noticeable one. My doctor finally ordered some comprehensive cardio tests for me, and even hooked me up to a Holter (sp?) machine to monitor my hearbeat for 24 hours during and after excercise and everything in between.

During the moments I feel the palpitations, the monitor didn't record anything irregular. So, it might just be that though we notice our heartbeat more, it isn't a concern.

I think you if you perceive your heart to quicken, become heavier, or have any irregular palpitations, you should notify your doctor and perhaps get some tests--if only for your own sanity that all is well.

Good luck.