Hello Customer (name blocked for privacy), this a common complication of cardiac surgery or any other surgery that impairs the lymphatic drainage of a part of the body. This is called lymphoedema.Let me elucidate how this happens:

The lymphatic system is a significant pathway for the drainage of fluid,large protein molecules and white blood cells from the interstitial spaces within capillary beds. Lymphatic capillaries lie in the dermis and subcu- taneous fat, in the fascial planes between muscles and in perivascular tissues. Lymphatic vessels transport lymph from these areas through regional lymph nodes towards the thoracic duct. Lymph returns to the venous circula- tion via the termination of the thoracic duct at the left internal jugular vein close to its junction with the left subclavian vein ( in close proximity to the upper arm ). Impaired drainage of lymph from a limb, usually due to obstruction of the system, leads to the accumu- lation of fluid and protein in the subcutaneous tissues with eventual irreversible fibrosis and swelling, known as lymphoedema .

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