My father has a pacemaker/difibrillator.  He had open heart surgery when he was 59/ double pypass and a valve transplant.  He is 78 now.  Shortly after he eats or drinks anything, he feels a heaviness in his stomach (no pain) and shortness of breath.
HelloWelcome to Chat Doctor. He has got a history of heart disease with bypass surgery and valve replacement with a defibrillator. The symptoms he is getting may be due to acidity. But a cardiac cause should be ruled out. Please do an ECG and 2d echo. ECG will show the electrical activity of the heart indicating he's functioning of the pacemaker /defibrillator.2 d echo will show the structure of the heart, its valves, the functioning of the valves, the leak between the valves and the pumping function of the heart. Please do the above and revert with the findings. Wishing him good health Regards