hello, i can understand your concern. the most common cause for unilateral edema would be venous insufficiency. i would require the following answers before proceeding further. does the swelling pit on pressure??? does the swelling reduce in the morning??? are there any visible veins which are enlarged on the legs???? does it hurt on applying pressure?? is the skin over the area warm??? any colour changes are seen over it??? kindly get a doppler study done for the limb affected. do get back with the reports and the answers for the questions asked for further management. if you notice any sudden increase in the swelling or it gets tense or the colour changes to blue kindly get evaluated by a doctor immediately. feel free to ask further queries. thanks for choosing HCM