What Causes Loss Of Consciousness And Tightness In Chest Along With Coughing?

During physical exercise (P.E. class at college) my daughter became quite faint, experienced several seconds of "darkness", and tightness in her chest. She stopped the activity and began coughing. This has been ongoing for a number of years. She also experiences severe coughing after times of extended, hard laughter, and running or jogging.