Hi. From the I formation you give looks like she has lung as well as heart issues. Swelling in legs is due to fluid retention in body which can be due to her heart issue, either heart pumping being low or heart being stiff. Also if the lung disease has been there for a long time it can affect the right sided chambers of the heart which again can cause fluid retention, swelling etc. Do you have any Echo done recently to assess the heart? Does she have breathlessness? How bad is the lung disease? Does she require oxygen at home or regular nebulisations? Dytor is a diuretic, that is it makes the person pass more urine and that is how the excess fluid in the body is got rid off and swelling decreases. Also at this age it can also be a sign of urinary tract infection. Elderly females may have urine infection but may not have high fever but will have other symptoms like burning while passing urine, tiredness. If the swelling of legs is worsening even with oral dytor she needs further evaluation