July 01, 2010

Q&A: Pharmacologic Stress Echocardiography

Stress echocardiography (echo) is an established technique for assessing coronary artery disease. It has been used for diagnosis and assessment of probable coronary artery disease, for risk stratification and to guide revascularisation procedures.

This article is for Medical Students & Professionals
This is a Question & Answer revision article designed for medical students and professionals preparing for the PLAB, MRCP or USMLE examinations. They are based on actual questions from these examinations. You may find the Cardiovascular Disease article more useful, or one of our many articles on Diseases & Conditions, Medical Syndromes, Health & Wellness or Home Remedies.
In this article:
Pharmacologic stress echocardiography
MCQ exam: clinical scenario
MCQ exam: answers
MCQ exam: explanation

Pharmacologic stress echocardiography

Stress echocardiography is a cost-effective tool for the modern non-invasive diagnosis of coronary artery disease. It has primarily been used for the diagnosis and assessment of patients presenting with chest pain in whom there is an intermediate probability of coronary artery disease. In addition, it is used for risk stratification (for example, prior to non-cardiac surgery) and to guide revascularisation in patients with known ischaemic heart disease.

Several physical and pharmacological stresses are used in combination with echocardiographic imaging. The safety of a stress is (or should be) a major determinant in the choice of testing.

Pharmacologic stress testing can be performed using either chronotropic/inotropic agents which work on the heart to increase heart rate and strength of contractions; or using vasodilator agents which affect cardiac blood vessels causing arteries to dilate and increased blood flow.

MCQ exam: clinical scenario

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

MCQ questions & answers on medicalnotes.info

MCQ exam: answers

The correct answer is B.
Adenosine is the most likely pharmacologic agent.

MCQ exam: 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.

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