Retinal evaluation of patients on chronic amiodarone therapy

To determine whether retinal electrophysiologic changes can be detected and correlated with funduscopic findings in patients with the long-term use of amiodarone.

Eleven patients ranging in age from 52 to 67 years were recruited from the Stanford University Medical Center Department of Cardiology for ophthalmologic examination. Patients had received amiodarone at various dosages ranging from 100 to 800 mg daily for at least 15 months. Clinical indications for the use of amiodarone included atrial fibrillation, ventricular arrhythmias, and congestive heart failure. All patients underwent retinal electrophysiology studies (full-field and multifocal electroretinograms) in addition to a complete ophthalmologic examination and fluorescein angiography.

No patients were found to have significant vision loss. Funduscopic examination and fluorescein angiography showed mild age-related changes in four patients, three of whom had nonspecific foveal pigmentary alterations. Multifocal and full-field electroretinograms were mostly unremarkable, and the mildly subnormal findings in a few patients showed no consistent pattern to suggest a toxic cause. Dosage, duration of amiodarone exposure, patient age, and underlying cardiac disease did not appear to correlate with these findings.

No significant adverse retinal funduscopic changes or electrophysiologic effects could be correlated with amiodarone exposure in this small series of patients. Routine electrophysiologic and funduscopic screening of patients receiving amiodarone does not seem warranted, although future prospective controlled studies may be required to exclude the possibility of progressive abnormalities in patients with preexisting age-related macular degeneration.