Acute onset of bilateral visual loss during sildenafil therapy in a young infant with congenital heart disease

Abstract

We report a case of posterior non-arteritic ischaemic optic neuropathy (NAION) causing bilateral visual loss in a 7-month-old female infant, after a therapeutic course with sildenafil, a phosphodiesterase type 5 inhibitors (PDE5i). The patient was affected by a complex cyanotic congenital heart defect and had undergone cavopulmonary anastomosis (Glenn operation) 3 months ago. After 2 months of recurring chylothorax, a course of oral sildenafil was administered, with the hypothesis that pulmonary vascular resistances were increased. Approximately 4 weeks later the acute onset of visual worsening and poor pupillary light reflex prompted the diagnosis of posterior NAION. Despite a rapid cessation of PDE5i and systemic treatment with corticosteroids, no visual recovery was noticed at 2-year follow-up. NAION has been associated with PDE5i therapy in adults, but to the best of our knowledge it is almost unheard of in children. We suggest close monitoring of visual function in children undergoing treatment with sildenafil.

Ophthalmic findings in neonates receiving sildenafil

“…Two recent case reports identified NAION in young children receiving sildenafil. The first involved a 7‐month‐old who developed presumed bilateral posterior NAION 3 months after cavopulmonary anastomosis for cyanotic congenital heart disease and 4 weeks after onset of sildenafil therapy . The authors speculated sildenafil to be the causative agent; however, the retinal haemorrhages, venous engorgement and macular exudation described in this case are not commonly seen in posterior NAION.…”

“…In an adult population, sildenafil has been associated with transient mild visual blur, cyanopsia (blue‐tinged vision) and altered light perception. These reversible phenomena are thought to be due to altered phototransduction via an off‐target inhibitory effect on retina‐specific phosphodiesterase type 6, or retinal vascular auto‐regulatory changes . In addition to these transient phenomena, there have been many case reports purporting increased risk of central serous chorioretinopathy (CSCR), and permanent visual loss from non‐arteritic anterior ischemic optic neuropathy (NAION) .…”

Visual Side Effects Linked to Sildenafil Consumption: An Update

“…Of the above mentioned drugs, sildenafil is the one that has exhibited a higher incidence of visual side effects, given that it is only 10-fold more potent on PDE5 than on PDE6 [ 11 , 31 ]. As an example, numerous case reports describing ocular side effects associated with the consumption of sildenafil can be found in the medical literature ( Table 2 ) [ 32 , 33 , 34 , 35 , 36 , 37 , 38 , 39 , 40 , 41 , 42 , 43 , 44 , 45 , 46 , 47 , 48 , 49 , 50 ]. Its nature of use, its frequent use, a possible overdosage beyond the recommended optimal dose and the advanced age of the patient with frequent associated vascular pathologies makes it necessary to mention some of the adverse effects observed by the intake of sildenafil.…”

“…Because PDE5 is expressed in the endothelial and smooth muscle cells of the choroidal and retinal vessels, sildenafil may affect ocular blood flow [ 63 ]; thus, it is reasonable to think that may cause other visual symptoms apart from those derived from the nonselective inhibition of PDE6 [ 11 , 64 ]. In fact, severe effects such as an increase in intraocular pressure (IOP) [ 65 , 66 , 67 ], retinal and choroidal vasodilation and altered blood flow [ 68 , 69 ], and nonarteritic anterior ischemic optic neuropathy (NAION) [ 45 , 70 , 71 ] have been reported as a consequence of the intake of sildenafil. Since many of the symptoms are dose-dependent, further studies are needed to establish the dose above which adverse effects occur in sildenafil users.…”

Ocular Effects of Sildenafil in Naïve Mice and a Mouse Model of Optic Nerve Crush

“…Furthermore, although most of the reported patients had vascular risk factors for NAION overlapping with erectile dysfunction, not all did so, and in some cases, unilateral NAION developed within minutes to hours of ingestion of sildenafil. 17,18,[24][25][26][27] There is still a paucity of convincing epidemiologic evidence linking NAION with the use of erectile dysfunction drugs. [28][29][30][31] However, a recent study found that in patients using these drugs, the odds ratio for acquiring NAION increased 2-fold.…”