53 yr old female experiencing breathlessness in short walk. Though she is overweight, she takes a 1 hr walk everyday. We have got heart checkup done everything is okay, but the problem is persistent since 4-5 year. She also has cholesterol and high bp. What could the issue be? Should we consult a pulmonologist or a cardiologist? Spoken to our gen physician multiple times he says this is only a problem due to lack of stamina. Could this be something else?