Hello, As you are COPD, there is a chance of getting into fatigue, because the respiratory system consumes the maximum amount of energy of the body. Also, what is the x-ray or CT of lungs are telling, are there are visual changes noticed. If any we need to workout on it. Usually a good pulmonary rehabilitation plan is helpful for most COPD patients. Also, you have a pacemaker so we need to understand the physical status of the overall functions of the heart and lungs and based on it an individual pulmonary rehabilitation plan has to be decided. Usually, COPD patients tend to breathe from mouth and less from the nose. So doing deep breathing exercises, Forced expiratory breathing, segmental breathing, core strengthening, low intensity general exercise etc. A good plan works well, when a keen observation is made on day to day basis. In my clinical practice of over 12 years, COPD patients respond well to pulmonary and cardiac rehabilitation combination with a physician and physiotherapist team. Hope I have answered your query. Let me know if I can assist you further. Take care Regards, Jay Indravadan Patel, Physical Therapist or Physiotherapis