Fluke Biomedical ProSim 8 Series, Руководство пользователя

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ProSim™ 8
Users Manual
A-4
Bundle Of HIS
A collection of nerves (about 1 cm in length) that lies just below the AV node in
the heart. Part of the heart’s electrical conduction system. With the AV node,
forms the AV junction . Below the bundle, the nerves divide into left and right
branches.
Computational Constant
Pertaining to cardiac output. Sometimes called calibration coefficient.
Cardiac
Of, near, or pertaining to the heart.
Cardiovascular
Of, pertaining to, or involving the heart and the blood vessels.
Capillary
One of the minute blood vessels that connect the arteries and veins.
DC component
See R-Value
ECG
An electrocardiogram (ECG) records the electrical signals of the muscles of the
heart—the depolarization and repolarization of the myocardium . Wires from an
ECG machine are connected to small plastic or metal cables called leads, or
electrodes. Put on the chest, the wrists of the right and left arms, and the left leg
at the ankle, these electrodes transmit signals to a recorder. The recorder makes
lines in the shape of waves on graph paper in the ECG machine, follow the
heart's electrical activity (rate) and its rhythm (beat). Each contraction of a normal
heart causes a normal sinus rhythm (NSR) waveform , also referred to as the P
QRS T waveform.
Frequent Multifocal PVCS
A sequence that includes a left-focus PVC followed by normal beats, alternating
with a right-focus PVC followed by normal beats. Frequent multifocal PVCs are
initiated by a number of different ectopic pacemakers in the ventricles , with
events occurring at least five times per minute, and usually more often.
Gram
A metric unit of mass and weight, equal to one-thousandth of a kilogram , about
0.035 ounces.
Heart Block: First, Second, and Third Degree
Three heart-block simulations, running as repeating sequences. A heart block is
a condition wherein the signal generated by the SA node is delayed or is blocked
(partially or completely) in its journey to the ventricles . Because this condition
typically occurs at the AV (atrioventicular) junction, a more precise term for heart
block is atrioventricular block. When the conduction time from the atria to the
ventricles becomes delayed (usually resulting in a P-R interval greater than 0.20
seconds), it is referred to as a first-degree block. When impulses from the atria
occasionally do not reach the ventricles, the block is considered partial or
incomplete and is referred to as a second-degree block. Finally, when no
impulses whatsoever are able to enter the ventricles from the atria, the heart
block is complete and is referred to as a third-degree block. As a consequence of
a third-degree block, the atria and the ventricles beat at their own separate rates.