I Have A 11 Year Old Daughter. She Was Born

I have a 11 year old daughter. She was born with a heart murmur. I'm currently going to school to obtain my LVN. We where learning about CHF. My concern is her fingers. They look like clubbed finger (at least in only 3 of them). She joined cross country and had an episode of SOB and said she couldn't see for about 5min. That everything went pitch black at th end of her race, I thought it might have been hyperventilation. Is there any relation with all this episodes? Is it possible for her heart murmur cause her clubbed fingers? Was I right on her hyperventilation?