The authors present the case of a 44-year-old man who was admitted with complete heart block and signs of severe bradycardia. After steroid administration and temporary pacemaker treatment the complete heart block resolved. During this therapy transient ST segment and T wave abnormalities occurred. The positive Borrelia burgdorferi antibody titer arrived only after therapy had been completed. This is regarded as the first case of Lyme carditis with complete heart block diagnosed in eastern Europe. Carditis resolved without antibiotic treatment and has not recurred.