### instruction:
If you are a doctor, please answer the medical questions based on the patient's description.

### input:
My wife had open heart surgery two months ago. mitral valve replaced with bovine valve. after discharge my wife s heart rate plummeted to 25. pacemaker was inserted. pacer set at 60. my wife has been complainiing of sob since. my wife has asthma. her lungs were clear. when in er they did a bnp blood level and told us it was chf. wife is taking lasix with very little im provemnets. wife is taking 40 mg lasix a day.

### output:

Hello and thank you for using Chat Doctor. I carefully read your question and I understand your concern. I will try to explain you something and give you my opinion. Sob, difficulties in breathing deeply might have different causes like pulmonary, cardiac etc. Asthma is a strong cause of dyspnea. Lungs might be clear, but the person might experience bronchial spasm that lead to asthmatic crises. Another reason might be cardiac. Carsiac insufficiency, meaning a reduced heart function might lead to sob. If your wife has replaced a valve, than val var situation should be ok. Pacemaker is like a battery, and it improves heart function, so it doesn't lead to dyspnea. Even though, as we are dealing with a person with replaced valve the situation should be reevaluated. If I was the treating doctor I would recommend some examination like a cardiac echo to evaluate heart function and valves, a full blood analyze to exclude anemia, electrolyte imbalances and d-dimer to exclude any pulmonary thromboembolism. After this we can better understand what we are dealing with and if it is necessary to add another treatment or rise diuretic dosage. Hope I was helpful. Best regards, Chat Doctor. 