You are notified about an abnormal ECG in a 76-year-old man admitted to the acute care unit with infective endocarditis of his prosthetic aortic valve:

• Sinus rhythm with Mobitz I second degree AV block – Ventricular rate 82/min 
• Right bundle branch block

The following tracing is recorded two hours later: 

• Sinus rhythm with complete heart block
• Escape rhythm, 47/min, with wide QRS, probably junctional escape rhythm with right bundle branch block pattern given previous conducted QRS complexes with similar morphology