A 45-year-old woman with no prior medical issues presents to her family physician for several weeks of progressive fatigue and dyspnea on exertion. Vital signs taken with an automatic blood pressure (BP) cuff show a BP of 85/56 mm Hg and heart rate of 36 beats/min. An ambulance is called and she is taken to the nearest emergency department because of her severe bradycardia. Results of a 12-lead ECG obtained on arrival is shown below:
Questions to consider:
1. What does the ECG show and what is the reason for the abnormality?
2. How do the ECG findings explain the patient’s bradycardia and relative hypotension as assessed by the automatic BP cuff?
3. What further diagnostic testing is warranted?
4. How should the patient be treated?