Central retinal vein occlusion in a patient after being commenced on sildenafil citrate for pulmonary arterial hypertension.

A 75-year-old female was commenced on sildenafil for the treatment of pulmonary arterial hypertension (PAH) secondary to chronic obstructive pulmonary disease (COPD). She reported blurring of vision within 72 hours after starting treatment and was found to have a central retinal vein occlusion (CRVO). Such an occurrence is the second case reported to date, and we review the possible mechanisms and literature on the subject.