The music playing while Athan takes Eliza to dinner is Haydn's string quartet Op 76 "Emperor" second movement (Poco Adagio Cantabile), which is the melody of Germany's national anthem. It was originally composed for a Hungarian count and published in 1799, exactly 100 years before the episode is set.
A Deep Vein Thrombosis (DVT) is a local clotting of the blood in the leg.
An aneurysm is an enlargement of a blood vessel due to a weakness in an the artery wall, which may eventually burst.