DEFINITIONS There are numerous terms used in pacing. Some of these are listed below:
Action Potential: The action potential is brought on by a rapid change in membrane
permeability to certain ions, with unique properties necessary for function of
the electrical conduction system of the heart.
Automaticity: Is the ability of the cardiac muscles to depolarize spontaneously, i.e. without
external electrical stimulation from the nervous system.
Ampere (AMP, A): Is a measure of electrical current flowing past a point in a conductor when
one volt of potential is applied across one ohm of resistance. In pacing, these
currents are so small that they are expressed in thousandths of amperes
(milliamperes, mA) or in millionths of amperes (microamperes, μA)
Amplitude:
The maximum absolute value attained by an electrical waveform, voltage or
current. The amplitudes of pacemaker output pulses are expressed in volts
(the difference in electrical potential), or in milliamperes (the measure of the
electrical current flow).
AV Interval / Atrioventricular Interval, AV Delay: In a dual chamber pacemaker mode the AV Interval is the period of time
between an atrial event (sensed or paced) and a scheduled paced
ventricular event. It is typically measured in milliseconds. The AV Interval can
also be thought of as the pacemaker equivalent to the PRinterval in normal
conduction.
Liverpool Hospital
Intensive Care: Learning Packages Intensive Care Unit
Pacemaker Learning Package LH_ICU2016_Learning_Package_Pacemaker_Learning_Package
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