Pea, I had a ECG in my last pregnancy, which showed up a slight heart murmur. I only started getting symptoms because of the extra strain your heart is under when pregnant. Apparently one of my valves goes "whoosh", beyond that I have no idea what it means! I've never had any problems with it aside from during pregnancy, and I've not needed any treatment or monitoring. When pregnant I get palpitations that can be strong enough to make me gasp, and that's it.
Did the hospital say who had said it's urgent? It could well be that the scan department said it was urgent, but not the cardio doctor who grades it. I used to do outpatient for a different department, and we would often get referals from GPs saying things were urgent, when they were actually just annoying for the patient, so they got graded back down to routine so as not to jump ahead of someone who was at risk.
Even if the cardio doctor says it's urgent, that could well be because you're pregnant. If there is any issue, they'll need it under control before labour, so they'd rather see you sooner.
I'm sure everything will be fine, but if you're worried about, phone back and tell them so. I used to get one of the nurses to call patients back if they were worried and the consultant was busy.
ION, last night I wasn't sleepy at my usual time, so I stayed up painting. DD1 decided that sleep was for the weak, so woke everyone up repeatedly last, and we still had to get up early for the plasterer arriving.
So now I feel ravenously hungry again! just had my second breakfast, eggs on toast, and it didn't even touch the sides. Going for porridge now!