Bilateral Cotton Wool Spots After Use of an Endothelin Receptor Antagonist

Abstract

Ambrisentan (Letairis; Gilead Sciences, Foster City, CA) is an endothelin receptor antagonist approved by the U.S. Food and Drug Administration for the treatment of pulmonary arterial hypertension. The authors describe the occurrence of bilateral cotton wool spots soon after initiation of ambrisentan treatment in a 29-year-old woman. Fluorescein angiography, optical coherence tomography, and fundus autofluorescence were performed. After discontinuation of ambrisentan, the cotton wool spots resolved without recurrence. To the authors' knowledge, this is the first report of retinopathy in the form of cotton wool spots associated with the use of an endothelin receptor antagonist.

Endothelins Inhibit Osmotic Swelling of Rat Retinal Glial and Bipolar Cells by Activation of Growth Factor Signaling

“…Different swelling-inhibitory intracellular signaling mechanisms in Müller and bipolar cells were previously suggested also for other receptor subtypes such as neurotrophic factor receptors [1]. However, the clinical use of ET receptor antagonists may have detrimental effects in the retina [21]. ET-2 has been shown to be a key molecule in endogenous survival pathways in the retina [19,31,38].…”

Cotton-Wool Spots After Use of Macitentan for Pulmonary Arterial Hypertension

“…6 In that case, visual symptoms and associated retinal hemorrhages were present, and CWSs resolved promptly with discontinuation of the medication. With a stable mean arterial pressure throughout the observation period in both reported cases, no other cause for CWS appearance was discerned.…”