MRCP 1 Question 10

A 70 year old with chronic lung disease and with a strong family history of ischaemic heart disease presents with atypical chest pain.

An ECG is suggestive of ischemia. In view of the history of chronic lung disease a pharmacologic stress echocardiography is organised.

What is the most likely pharmacologic agent to be used in this case?

a) Dipyridamole
b) Adenosine
c) Dobutamine
d) atropine
e) Arbutamine

ANSWER
The correct answer is B

Explanation

Adenosine is by far the most commonly used pharmacologic agent in nuclear perfusion imaging.

It can be used like dipyridamole and is typically infused at a maximum rate of 140 mg/kg per minute during imaging.

The mechanism of action is probably identical to that of dipyridamole. However, adenosine has a much shorter half-life, and thus an antidote is usually not necessary in the event of an adverse reaction.