Brief Answer:
if related to the heart, would be both lower limbs

Detailed Answer:
HI, thanks for using healthcare magic

With a history of swelling at the end of the day, fatigue in the lower limb and use of a compression stocking, this may indicate that you have venous disease.

there are essentially 2 sets of veins in the lower limbs, those just under the skin called the superficial veins and those deeper called the deep veins. The superficial veins send blood to the deep veins and from there it goes back to the heart.

There are one way valves in the veins so blood should only flow in one direction. In persons with a history of prolonged standing or walking or a previous clot or trauma, these valves don't work as they should and blood backs up causing small or large varicose/enlarged veins.

The backing up causing swelling and a tired feeling at the end of the day. Compression stockings are used to try and help the blood get back to the heart.

This is not dealt with by a cardiovascular doctors, initially they are medically treated by a GP or internist
If surgery is required then a vascular surgeon would be best.

The heart can cause swelling of the ankles and legs but it would be both legs/ankles. Kidney ,liver disease or side effect of medication can also cause swelling of both lower limbs

Swelling of one lower limb implies that the cause is related to that limb itself- this can be varicose veins, trauma, infection, arthritis or a clot

I hope this helps, feel free to ask any other questions

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Brief Answer:
could aggravate the symptoms

Detailed Answer:
HI

Heat tends to cause veins to dilate so it can cause increased swelling.

The flight was not very long but if you did not get a chance to stretch and do small movements then that would also aggravate venous disease

Please feel free to ask anything else

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