Mon25October0844PM 19

A 78-year-old female patient is under the care of your supervising consultant on the coronary care unit.

She was admitted 24 hours ago with an acute anterior myocardial infarction. She underwent a primary percutaneous intervention with a good initial result. Post percutaneous coronary intervention the patient has remained haemodynamically stable.

However, the CCU sister calls you to see the patient as she noticed the heart rate was "slow" on the monitor. The patient had started to feel light headed and her blood pressure was 105/60 mmHg.

A 12 lead ECG reveals a bradycardia with a rate of 46 beats per minute with narrow QRS morphology. There are some non-conducted P waves and you note the PR remains unchanged prior to the non-conducted beat.

From the list below, which is the most appropriate next management step?

(Please select 1 option)

Monitor and observe

Transvenous cardiac pacing Correct

Transcutaneous cardiac pacing

Isoprenaline infusion

Atropine 500 micrograms

Explanation

The ECG findings are consistent with Mobitz type II second degree heart block.

There is a significant risk of asystole or complete heart block so temporary cardiac pacing is indicated in the first instance.

Mobitz type II or complete heart block does not respond to atropine. Atropine may be useful for sinus or junctional bradycardia.

Transcutaneous is the same as external pacing (via pads); it is terrible for the patient and should only be used as a holding measure in emergency. Transvenous is via the femoral or internal jugular vein.

Answer Statistics

1

9%

2

28%

3

10%

4

7%

5

47%

Times answered: 270