Many, many, many. The list is too long to write here. Common indications are chest pain, shortness of breath, heart murmur, and abnormal chest x-ray or ekg.
Many -- This is a curious question? You should not have to concern yourself about the diagnosis approvable -- that is your cardiologist responsibility -- but if you have a concern about your heart, then you should see a cardiologist and get your question and concern answered -.