<s>[INST] I had the bypass heart surgery and i am also a smoker and recently i noticed that my feet were swelling and also i had shortening of breath and my doctor has prescribed me water pills and the swelling has gone and doctor took my xray of chest and told me that i was retaining water in my lungs,does this means that i had chest infection or due to heavy smoking or drinking once a week has caused the problem or do you think that i am having a heart failure.? [/INST] Thanks for your question on Chat Doctor. In my opinion it is due to cardiac failure only. In cardiac failure circulation of fluid (water) is disturbed so fluid tend to accumulate in certain places in following order.1. Legs2. Abdomen3. Lungs. So gravity dependent fluid accumulation is seen in cardiac failure. So your fluid in lung is the sign of failure only. Better to consult cardiologist and start diuretics and cardiac isotopes. Restrict your fluid intake to 1.2 to 1.5 liters per day. Avoid excess salt. </s>