Can having aorta valve stenosis cause a lot of gas is there a connection?

Not usual: Not really. Typical symptoms of severe aortic stenosis are chest pain/pressure, shortness of breath and passing out. Fatigue may be seen. Cardiac chest pain may be felt as sensation of stomach gas or heart burn, but not actual gas.

No: There is no connection. But having a lot of gas is something that you should look into with your doctor. It could be related to the food that you eat- either because you cannot digest it properly (like beans, certain vegetables, dairy, etc.) or because you have a food sensitivity (like gluten/wheat or dairy). You can try eliminating some of these foods to see if your symptoms improve.