Atrial Fibrillation

Atrial fibrillation is a common occurrence in the medical examination. It can appear either as a short case examination or part of the long case examination.

Atrial fibrillation can be easily missed especially if there is bradycardia or tachycardia. However with practice, it can be detected rather easily. 

The 3 key features of atrial fibrillation that a student should be able to identify are:

1. Irregularly irregular rhythm

2. Variable pulse volume

3 Pulse deficit*

* A pulse deficit is when there is discrepancy between the peripheral pulse rate and the heart rate. Depending on which medical article you refer to, pulse deficit can vary between 5 to 10 beats per minute to be considered significant. 

Once atrial fibrillation is detected, a good student will go on to try to determine its cause or associated features:

1. Thyrotoxicosis

- look for signs of hyperthyroidism: exophthalmos, hand tremors, proximal myopathy, goitre with bruit

2. Elderly

- Elderly patients are more prone to have atrial fibrillation

3. Valvular heart disorders

- Examine the heart for any murmurs; commonly mitral stenosis or even mitral regurgitation

4. Heart failure

- Chronic atrial fibrillation may progress to heart failure especially if the heart rate is inadequately controlled. Conversely, patients with heart failure are also prone to develop atrial fibrillation. 

CCE.