Hi, welcome to HCM.
It is not a stroke
or myocardial infarction
. It could be any thing like retinal detachment
, vitreous haemorrhage or choriadal detachment. In rare possibility is embolism
to retinal artery.
Whatever is cause you need to consult your ophthalmologist for emergency examination and treatment. It is acute emergency situation.
Hope I have answered your query.