Fluke Biomedical ProSim 4 - Manual (Page 46)

ProSim™ 4
Users Manual
A-6
Sinus Arrhythmia
Beats that are normal, but triggered at an irregular rate, from 60 BPM to 100
BPM.
Sinus arrhythmia occurs when the SA node paces the heart irregularly. Typically,
the heartbeat increases with each intake of breath and decreases with each
exhalation (a condition most commonly found in young children and the elderly).
Ventricle
A small anatomical cavity or chamber, as of the brain or heart, especially (1) the
chamber on the left side of the heart that receives arterial blood from the left
atrium and contracts to drive it into the aorta, and (2) the chamber on the right
side of the heart that receives venous blood from the right atrium and drives it
into the pulmonary artery.
Ventricular Fibrillation
An irregular ventricular waveform, coarse or fine. Coarse and fine ventricular
fibrillations occur when the electrical signals in the ventricles are chaotic, and
multiple, ectopic, ventricular pacemakers are firing erratically. There are no real P
waves and no clear R-R interval. Ventricular fibrillation waveforms are irregularly
shaped. Ventricular fibrillation is a life-threatening condition; usually in such
situations a defibrillator is applied immediately to return the heart to its normal
rhythm.
Ventricular Tachycardia
A faster-than-normal rhythm of beats (160 BPM) originating in the ventricles,
similar to type-1 (left-focus) PVCs. Ventricular tachycardia is a life-threatening
arrhythmia in which one or multiple, ectopic, ventricular pacemakers in the
bundle branches, Purkinje network, or ventricular myocardium are firing in a
heart beating more frequently than 110 times a minute. In some cases the heart
will be beating at a rate above 240 BPM. Ventricular tachycardia usually occurs
in cases of extreme cardiac disease and often initiates or degenerates into
ventricular fibrillation. This type of tachycardia can reduce cardiac output by as
much as 25 % due, in many cases, to the lack of an atrial “kick” and therefore the
lack of a complete filling of the ventricles with blood prior to ventricle contraction.
Volt
The International System unit of electric potential and electromotive force, equal
to the difference of electric potential between two points on a conducting wire
carrying a constant current of one ampere when the power dissipated between
the points is one watt.
Waveform
(1) The mathematical representation of a wave, especially a graph of deviation at
a fixed point (baseline) versus time. (2) On an ECG tracing or output, the size,
shape, and distance (in milliseconds) of a P-QRS-T complex.
Wavelength
In a periodic wave, the distance between two points of corresponding phase in
consecutive cycles.