Let us know what the vet says. Pinta and others can probably give you a better opinion, though.
Worth checking out but it is hard to accurately diagnose heart problems and asthma. Ultrasound and xrays can help diagnose heart. I don´t think there is any test to diagnose asthma. We have tried drugs that are used for asthma, like prednizone, dexamethasone and terbutaline and assumed asthma when the pig improved.
You´ll have to decide yourself.
Our vet will listen to the lungs first and if they sound off and it´s a chronic situation will go the xray route first. If the xray shows something suspicious that she feels requires more info - then an ultrasound is ordered.
Pigs that are been obviously sick with heart disease symptoms get an xray before being given Lasix. Those xrays show air in stomach, enlarged liver and congested lungs. Sometimes the heart isn´t even visible if the congestion is really bad. Those are enough indications to give the pig Lasix and assume heart problems. If the pig improves with Lasix, it is a confirmation(as much as is really possible most times) of heart problems.
The girls--especially Shelby--sometimes breathe very noisily when they are in a temper and especially when they don´t want to be held. Shelby does this when she panics after I take her out and she thinks the other girls are going to get a treat in her absence. It has never happened! She is the family matriarch. I wouldn´t dare...