Although branch retinal artery occlusion (BRAO) is a relatively benign disease in terms of permanent visual impairment, the associated systemic diseases confer significant morbidity and mortality. The following systemic disorders can be found among patients presenting with a retinal artery occlusion: hypertension (59%), significant atherosclerotic cardiovascular disease (21%), diabetes mellitus (15% to 21%), left-sided valvular heart disease (5%), and cerebrovascular accidents (5%). These underlying systemic diseases are often responsible for a significant reduction in life expectancy and are in many cases potentially treatable conditions. A thorough cardiovascular examination (including a carotid duplex ultrasonography) may identify these occult diseases, and a prompt and effective treatment may improve the quantity and quality of patients' lives by reducing the risk of further arterial occlusive events.