Bradycardia after high-dose intravenous methylprednisolone therapy.

In 5 consecutive patients with rheumatoid arthritis who received intravenous high-dose methylprednisolone (MP) therapy (1 g daily for 2 or 3 consecutive days), a decline in pulse rate was observed, most pronounced on day 4. In one of the 5 patients the bradycardia was associated with complaints of substernal pressure. Reversal to normal heart rate was found on day 7. Electrocardiographic registrations showed sinus bradycardia in all cases. No significant changes in plasma concentrations of electrolytes were found. Careful observation of patients receiving high-dose MP is recommended. High-dose MP may be contraindicated in patients with known heart disease.