Ophthalmological consequences of cyanotic congenital heart disease: vascular parameters and nerve fibre layer

Abstract

Background: This study investigated the long-term ophthalmological consequences of cyanotic congenital heart disease (CHD).

The eye in CHD

“…We have previously found global retinal nerve fibre layer thickness below the normal range in half of our study cohort (6/13); however, owing to a small sample size, these results were not significantly different from controls. 7 Retinal nerve fibre layer thickness correlated with cerebral white matter volume, implying potential neuropathological effects of chronic hypoxaemia. In this study, we also reported a high whole-blood viscosity in cyanotic patients, which was negatively correlated with retinal nerve fibre layer thickness, suggesting that viscosity may play a significant role in tissue perfusion and ocular pathogenesis in the cyanotic CHD group.…”

“…5,6 These less common events are more likely to affect visual acuity than vessel tortuosity; hence, the majority of cyanotic patients have normal visual acuity, despite mild changes to the retinal vasculature. 7,8 The abnormal retinal vasculature is probably in response to the chronic hypoxia and erythrocytosis that is prevalent in cyanotic CHD patients. 8 Relief of the cyanotic condition after surgical repair almost always results in the retinal vasculature returning to normal.…”

“…12 Furthermore, findings show that cyanotic CHD patients also have increased branching of retinal vessels, leading to an overall complex vasculature bed. 7 This has been associated with poor vessel function and blood perfusion, ultimately leading (potentially) to retinal vessel occlusion. 13 Retinal ischaemia secondary to chronic cyanosis may also cause neovascularisation of retinal and iris structures, mainly through upregulation of vascular endothelial growth factor.…”

“…The most common malformation in cyanotic CHD patients is retinal venous dilation and vasculature tortuosity 3 , 4 (Fig 2); less common findings include retinal haemorrhages, macular oedema, central retinal artery, and vein occlusion 5 6 These less common events are more likely to affect visual acuity than vessel tortuosity; hence, the majority of cyanotic patients have normal visual acuity, despite mild changes to the retinal vasculature 7 8 The abnormal retinal vasculature is probably in response to the chronic hypoxia and erythrocytosis that is prevalent in cyanotic CHD patients 8 .…”

“…Furthermore, findings show that cyanotic CHD patients also have increased branching of retinal vessels, leading to an overall complex vasculature bed 7 . This has been associated with poor vessel function and blood perfusion, ultimately leading (potentially) to retinal vessel occlusion 13 .…”