This case report from Brady Pregerson, MD,
A patient in their mid-50’s is sent to the hospital ER for an abnormal pre-op ECG. He denies any symptoms other than right elbow pain for which he was supposed to have surgery at an outpatient surgery center. The surgery was cancelled because the pre-op ECG was abnormal showing a heart rate in the low 40’s. The patient does not know what his baseline heart rate is and he has not been in your ER before so you are unable to look it up.
Vital signs are normal except for a pulse of 42. The physical exam is otherwise normal.
An ECG is done:
What is the most likely rhythm in this patient?