Wegener's granulomatosis is a systemic inflammatory disorder of unknown cause that usually affects the upper and lower respiratory tracts as well as the kidney. Cardiac involvement is rare, although electrocardiographic abnormalities, coronary artery vasculitis, cardiac arrhythmias, and myocardial infarction have been reported in the literature. A 27-year-old female patient with Wegener's granulomatosis in remission is described in whom complete heart block developed in the 13th month of treatment with cyclophosphamide. A temporary pacing was applied and pulse methylprednisolone and cyclophosphamide were commenced. On the ninth day of treatment, normal sinus rhythm was achieved. In conclusion, cardiac rhythm abnormalities should always be kept in mind both in the diagnosis and follow-up of Wegener's granulomatosis.