This happens because there's increased pulmonary congestion while lying down, and in left-sided ventricular heart failure, the pulmonary circulation is already overloaded.
When that happens it can cause periorbital ecchymosis, also called raccoon eyes, because of the dark rings of blood that can be seen in the soft tissue around the eyes.
" I'll grind some herbs you can mix with wine to bring down your fever. Come back on the morrow and I'll put a leech on your eye to drain the bad blood" .
As the western sky turned the color of a blood bruise, she heard the sound of approaching horses. Dany rose, wiped her hands on her ragged undertunic, and went to stand beside her dragon.