59 year old female with RA, hypothyroidism, recently diagnosed severe sleep apnea, 5'5 and 190 lbs. Bipolar disorder. Meds include Celexa, Folic Acid, Prednisone and Methotrexate. For the past 6 mos. about once a week I get a fluttering feeling underneath lower left breast. Never had indigestion or heartburn. Could this be heart related.