37 female.quit smoking 14 yrs ago.normal bmi,cholesterol,ekg,bp. have 5-10 sec. pains in chest and sternum.pcp says heart ok.odds of cardiac problem?

Consider..: If your doc has ruled out the obvious heart problems and risk factors for them (other than history of smoking), then I would consider other diagnoses like GERD or costochondritis, even your anxiety can cause this.

Relax: You yourself localize the pain to your sternum. Such pains are not of cardiac origin. Especially, you should be very, very proud of having quit smoking.