A 69 year old underwent open-heart surgery 48 hours ago. He was discharged to the surgical floor after the chest tubes were removed. At night, the nurse suddenly pages you because the patient has a BP of 68/45, RR 22 and a Pulse oximetry of 92. She tells you that the heart rate is fast but she cannot tell what the exact rate is. The patient had been fine all day and also had a CXR done early in the morning, which was unremarkable. An ecg strip from the monitor is shown below.
The next step in the management of this patient is:
c. IV amiodarone
d. IV digoxin