A 75-year-old man with a medical history of sick sinus syndrome and left bundle branch block presented for evaluation of chest pain. The patient had a dual-chamber permanent pacemaker. Figure 1 shows his electrocardiogram (ECG).
The Focus on ECGs section, published in the Texas Heart Institute Journal, presents a challenging ECG, a quiz, and a short comment on the interpretation of the ECG. This blog provides a collaborative opportunity to discuss each case in an effort to share the knowledge and the art of interpreting ECGs. Each discussion will close 2 weeks after publication.