alternating current (AC) interference
Electrical interference that appears as small, uniform spikes on ECG tracing.
Device on the electrocardiograph that magnifies or enlarge the heart's electrical impulses so they can be recorded.
Unwanted changes in an ECG tracing caused by movement, machine malfunction, or other factors.
Atrioventricular (AV) node
Knot of specialized cells in the lower portion of the right atrium that produces the heart's electrical impulses
Leads that measure cardiac activity from one electrode on the body at a time; recordings are augmented (made larger) so they can be read.
Bundle of His
Small band of atypical cardiac muscle fibers that receive electrical impulses from the AV node
Devices made of a conductive material to pick up the electrical activity of the heart; sensors.
Forced vital capacity (FVC)
Measurement of the maximum volume of air that can be expired when the patient exhales forcefully.
Device that detects and converts the amplified electrical signal into a tracing on the ECG machine
Ambulatory heart monitor that records heart activity during a 24- to 48- hour period.
Myocardial infarction (MI)
Heart attack; death of heart tissue caused by blockage of the heart's blood vessels.
Normal sinus rhythm (NSR)
Rhythm measurement that starts at the SA node, occurs within an established time frame, and follows an expected, est pattern.
Device that delivers electrical impulses to the heart muscle when the SA node is unable to do so
paroxysmal atrial tachycardia (PAT)
Sudden onset and ending of atrial tachycardial, 150 to 250 beats per min
Device that records the percentage of oxygen in the blood after a light source passes through arterial blood
Time interval necessary for an electrical impulse to cause contraction of the atria and begin contraction of the ventricles
Premature atrial contraction (PAC)
Condition in which an electrical impulse in the atria starts before the next expected heartbeat
Premature ventricular contraction (PVC)
Condition in which the ventricles receive an impulse prematurely and contract early
fibers from bundle branches that spread throughout ventricles carry electrical impulses, causing them to contract
ECG pattern that shows when the impulse moves through the ventricles and reaches the Purkinje fibers, depicting contraction of both ventricles
Time interval on ECG that shows the time needed for the ventricles to contract and recover
Time interval between the ventricular contraction and the beginning of ventricular relaxation
Standard limb lead
Device that carries the electrical impulses to the ECG and traces the electrical impulse of the heart in two different directions simultaneously
The process of making a test or procedure the same for everyone so that results can be compared to each other.
The use of exercise during electrocardiography to examine heart function under stress
normal, small upward curve that occasionally follows a complete ECG cycle after the PQRST; has unknown indication.
Disorganized, and ineffective twitching of the ventricles, resulting in no blood flow and a state of cardiac arrest
Three or more consecutive PVCs with heart rate exceeding 100 beats per minute
Measurement of the volume of air that can be expired when the patient exhales completely