I homeschool my children and have started a program which requires more reading aloud. I noticed that I feel a bit lightheaded/short of breath when I read aloud. It also makes me feel sleepy and yawn. I am concerned that this indicates an undiagnosed heart/lung disease. I did have a pretty extensive heart workup 18 months ago. EKGs, blood work, chest x-ray, echo, thallium stress test, 72 hour monitor, and a cath. I know that reading aloud made me feel tired even back then. If it was a lung problem would the cardiologist have picked up on something being wrong (I was in the hospital for 3 days and nights)?