Hello Janice , I am Dr. Arun and will be helping you today.The causes of hard and fast pounding of heart can be;1) Overactive thyroid gland (hyperthyroidism) 2) An abnormal heart rhythm (arrhythmia).3) Caffeine4) Medications5) Stress or anxiety.With your past medical history and concomitant medical issues, it is recommended that you should go to an urgent care clinic or emergency room to get an EKG for the cautionary purpose and to rule out abnormal heart rhythm. Please feel free for your follow up questions.
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