It sounds like your doctors ruled out the possibility of heart failure due to valve malfunction and blood
clotsBlood clots in the legs. Were any of your lower extremity veins taken out during surgery for a possible bypass surgery. If so, this could potentially explain the lower extremity swelling, which will resolve over time. If not, I would make sure that the kidney and liver functions are normal. This can be done with a simple blood test, and may have already been done. If, there are no identifiable causes, I would then suggest that this is post-operative edema and treat it conservatively with diuretics (as you are) and support stockings which can be ordered by your doctor or obtained over the counter at a local pharmacy.
I was instructed to elevate my foot above heart level twice a day for 20-30 minutes and place an ice bag on it, and wear a tube grip (tight sock) daily.
Although I am a CHF patient, it was first believed that the foot condition was a by-product of diabetes which I am also afflicted with, thanks to the medications I've been given. The final diagnosis in my case doesn't feel right but I've nothing else to go on for now.