[Sinus tachycardia after implantation of a pacemaker for 2 : 1 A-V block with bradycardia (author's transl)].

A demand pacemaker was implanted into a 74-year-old listless woman who was in congestive heart failure, obese and had diabetes mellitus. The ECG indicated a 2 : 1 A-V block (ventricular rate 40/min). Two days after implantation a sinus tachycardia of 98/min occurred and the diabetic metabolic state deteriorated. This was probably due to hyperthyroidism in a thyroid gland of normal size but varying uptake, and was possibly precipitated by the administration of iodine contained in an anti-asthmatic medication.