Pain and swelling in both the legs of my 90 years old dad. Is there a device that can massage his legs?

My 90+ year old dad has swelling in both the legs and has severe pain (heart and kidney conditions). He has heart problems (two heart attacks) and reduced kidney functions. He is able to walk around inside home. He is under heart medications and water pills. He has swelling in both the legs and has severe pain in both the legs. When I visit him once in a year I massage his legs and feet. Massaging the legs reduces his pains for few hours. Since I live U.S and he in India, I am not not able to take care of him on a continued basis.

Are there any mechanical devices like a pump that can periodically massage his legs.

Thank you very much,

Vasu