Hello and Welcome to ‘Ask A Doctor’ service. I have reviewed your query and here is my advice. After going through your medical details I understand your concern and I would like to tell you that gastric reflux can be very common cause of indigestion or heart fibrillation, to avoid this kindly avoid spicy, junk and caffeine containing food items. But we can t overlook reasons associated with pacemaker implantation. Heart fibrillation can also happen because of overworking or underworking pacemaker, electrolyte imbalance, not sensing properly or pacing imbalance etc which may require a set of evaluations. Kindly get an x-Ray , ECG, serum electrolytes and pacemaker assessment done and consult your treating Cardiologist for Fluroscopy and further management. Hope I have answered your query. Let me know if I can assist you further.