PURPOSE: To report the first two observations of bilateral paracentral acute middle maculopathy in the early postoperative period after cardiopulmonary bypass procedures. METHODS: Comprehensive ophthalmic examinations were performed, including best-corrected visual acuity, Humphrey visual field testing, dilated fundus examination, and optical coherence tomography. RESULTS: Two patients complained of unilateral vision loss after cardiac surgery involving cardiopulmonary bypass. Unilateral optic disc edema consistent with ischemic optic neuropathy was observed in the symptomatic eye of each patient, whereas scattered cotton-wool spots were identified bilaterally. In addition, optical coherence tomography imaging revealed bilateral paracentral acute middle maculopathy, correlating with visual field defects detected on automated perimetry in the asymptomatic eyes. CONCLUSION: Although symptomatic postoperative vision loss is a rare complication of cardiac surgery, intraoperative retinal microvascular nonperfusion as a consequence of extracorporeal circulation of blood may be a more common and under-recognized occurrence.