Possible heart arrhythmia.....

I’m 37 weeks and just had an ultrasound to she how baby is cooking. I noticed her heart flicker wasn’t the same but the tech didn’t say anything. We saw the midwife right afterwards and she mentioned that baby has a possible trigeminy, every third beat was a little off, we are waiting for a specialist to call us for an appointment to look into it further.

I’m not overly worried but I am wondering if anyone else has gone through this?

Also, we were told at every other ultrasound that baby has a good strong heartbeat, so why are we seeing this now?