A 40 year old male is admitted with acute inferior wall myocardial infarction, half an hour later BP is 80/50 mmhg and heart rate is 40/mt with sinus rhythm. The most appropriate step in the management of this patient would be -
Admission of normal saline 300 ml over 15 minutes
Immediate insertion of temporary pacemaker
Intravenous adminstration of atropine sulpate
Intravenous adminstration of isoprenaline 50 m/minute