User guide

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atrial fibrillation (uncontrolled)
Atrial fibrillation is uncontrolled when the heart rate response lies outside
normal limits (i.e. 50 to 120 beats per minute);. If AF is uncontrolled, cardiac
output may be compromised by periods of inappropriate tachycardia and
bradycardia. Pauses and arrests may also be evident with an uncontrolled
ventricular response.
atrial flutter (AF)
An abnormally rapid, well organised contraction of the atria at a rate of 250 to
350 per minute.
atrioventricular block
The failure to conduct the heart beat impulse from the atria to the ventricles.
atrioventricular node
Electrical relay station between the atria and the ventricles - electrical signals
from the atria must pass through this node to reach the ventricles.
atrium
one of the upper chambers of the heart
autonomic nervous system
Part of the nervous system that controls the involuntary activity of many
organs and muscles, including the heart.
autonomic tone
The effect of the autonomic nervous system on the heart rate.
bigeminy
Two ectopic beats separated by a normal beat.
bpm (BPM)
Beats per minute.
bradycardia
A slow heart rate. Appropriate bradycardia is a slow heart rate of more than
30 seconds duration between 40 and 50 beats per minute. Appropriate
bradycardia is normally associated with periods of resting and sleeping.
Inappropriate bradycardia is an abnormally slow heart rate.