Sinus bradycardia after intravenous pulse methylprednisolone therapy in patients with systemic lupus erythematosus.

Sinus bradycardia is reported as an adverse effect of high-dose glucocorticoid therapy. We report three cases of systemic lupus erythematosus, wherein intravenous pulse methylprednisolone was administered. The patients' average baseline heart rate was 72 beats/min, which decreased 30% from baseline at 61 h after beginning the therapy. The average minimum heart rate was 38 beats/min, and this rate continued for 169 h on average. No other causes for bradycardia were found, suggesting that the administration of glucocorticoid pulse therapy resulted in decreased heart rate.