A 59-year-old man is noted to have a complete heart block after mitral valve surgery and undergoes a VVIR pacemaker implantation on post-operative day 5. You are called routinely after the surgery to assess his post-procedure ECG:

• Underlying atrial fibrillation
• VVI pacing with occasional premature ventricular complexes and fusion beats
• VVI pacing is with abnormal morphology

Chest X-ray (CXR) was done after the previous ECG. The CXR confirms that the ventricular lead appears to have gone through a PFO (red arrow), through mechanical mitral valve (blue arrow), with the tip sitting at the basal lateral left ventricle (white arrow)

The patient is taken to the operating room and the lead was repositioned to the right ventricular apex. A post-operative ECG is as follow:

• Underlying atrial fibrillation
• VVI pacing with normal paced QRS morphology