A 48-year-old male was brought to our Emergency Department after a car accident due to syncope. His medical history included paroxysmal atrial fibrillation and a bicuspid aortic valve requiring aortic valve replacement with a mechanical prosthesis. At presentation, the electrocardiogram showed a new third-degree atrioventricular block. It was decided to implant a dual-chamber pacemaker, but the procedure was more challenging than expected. Fig. 1 shows the position of the leads at the end of the procedure. What is your diagnosis?

Fig. 1
figure 1

Radiograph showing final lead position in our patient

Answer

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