Amiodarone-induced acute respiratory distress syndrome masquerading as acute heart failure

Amiodarone use has been rarely associated with the development of acute respiratory distress syndrome (ARDS), usually in association with surgery or pulmonary angiography. In patients with preexisting left ventricular dysfunction, the diagnosis may be overlooked.

A 92-year-old woman with a history of atrial fibrillation who was on low-dose amiodarone presented to the Emergency Department with sudden onset of shortness of breath. The patient was started on treatment for acute heart failure based on the physical examination and the elevated brain natriuretic peptide level. Despite adequate diuresis, the patient showed no improvement. A chest computed tomography scan revealed acute interstitial pneumonitis. The patient received corticosteroids due to suspected amiodarone-induced acute interstitial pneumonitis resulting in ARDS. She returned to her baseline activity within 2 weeks of the therapy.

Although rare, clinicians should be vigilant for amiodarone-induced acute interstitial pneumonitis resulting in ARDS, as delay in treatment may result in a high risk of mortality. In addition, the development of ARDS occurred in our patient in the absence of precipitating factors such as surgery or pulmonary angiography.