NCCT NCET key terms

The legally defined set of tasks and duties an ECG technician may perform, set by state law, employer policy, and credentialing rules. Activities outside it must be referred to a nurse or physician.

The level of skill and caution a reasonably competent ECG technician would use in the same situation. It is the benchmark used to judge whether actions were appropriate.

The transfer of a specific task from a licensed clinician to an ECG technician who is trained and authorized to perform it. The delegating clinician retains overall responsibility for the patient.

Failure to provide the care a competent technician would provide, resulting in harm. It requires a duty, a breach of that duty, causation, and actual damages.

The United States federal law protecting the privacy and security of identifiable patient health information. It governs how ECG tracings, orders, and reports may be shared.

Any patient data that can identify an individual, including name, date of birth, medical record number, and the ECG tracing itself. It may only be accessed and disclosed for treatment, payment, or operations.

The patient's voluntary agreement to a procedure after being told its purpose, what it involves, and any risks. For a resting ECG the technician confirms understanding rather than obtaining formal consent.

The documented record of who handled a tracing or device and when, used when an ECG may become legal evidence or is part of a serious event investigation.

Verifying two independent identifiers, typically full name and date of birth or medical record number, before recording. Correct identification prevents tracings from being filed under the wrong patient.

A conductive pad or clip placed on the skin that picks up the heart's electrical signal and carries it to the ECG machine. Good skin contact is essential for a clean tracing.

Cleaning, drying, and lightly abrading the electrode sites to lower skin resistance. It reduces baseline wander, muscle artifact, and poor signal quality.

The conductive medium on a disposable electrode that bridges skin and sensor. Dried-out gel raises impedance and causes weak or noisy tracings.

The resistance to electrical current at the skin-electrode interface. High impedance produces artifact and poor waveform quality, so it should be kept low.

The four electrodes placed on the arms and legs, labeled RA, LA, RL, and LL, that produce leads I, II, III, aVR, aVL, and aVF. RL is the ground electrode.

The six chest electrodes V1 through V6 placed in defined intercostal positions to record the heart's electrical activity in the horizontal plane.

The space between two ribs, used to locate chest electrode positions. V1 and V2 sit in the fourth intercostal space, and V4 through V6 follow the fifth.

Incorrect attachment of limb or chest electrodes that produces abnormal-looking tracings, such as an inverted lead I or a negative P wave in lead II. Recognizing it prevents false interpretation.

Any electrical or mechanical interference on the tracing that is not from the heart, including muscle tremor, AC interference, and baseline wander. It must be reduced or documented.

Slow, wavy drift of the ECG baseline, usually from respiration, patient movement, or poor electrode contact. It can mimic or hide ST-segment changes.

Regular 60-hertz (or 50-hertz) electrical noise from nearby equipment or wiring that thickens the baseline. It is reduced by good skin prep, cable routing, and the notch filter.

High-frequency jagged noise caused by patient shivering, tension, or tremor. Warming the patient and relaxing the limbs usually improves the tracing.

A machine setting that removes a narrow band of frequencies, usually 50 or 60 hertz, to suppress AC interference. It should be used only when needed because it can distort waveforms.

The standard signal of 1 millivolt producing a 10-millimeter deflection, marked on the tracing. It confirms that amplitudes can be measured accurately.

The rate at which the ECG is recorded, usually 25 millimeters per second. At this speed one small box equals 0.04 second and one large box equals 0.20 second.

The smallest grid square on ECG paper, representing 0.04 second horizontally and 0.1 millivolt vertically at standard settings. It is used to measure intervals and amplitudes.

A grid square made of five small boxes, representing 0.20 second horizontally. Counting large boxes between R waves gives a quick estimate of heart rate.

The number of ventricular beats per minute. It is estimated by dividing 300 by the number of large boxes between R waves, or by counting beats in a six-second strip and multiplying by ten.

The time between two consecutive R waves, used to assess rate and regularity. A varying R-R interval suggests an irregular rhythm such as atrial fibrillation.

A normal rhythm originating in the sinoatrial node, with upright P waves in lead II before each QRS and a rate between 60 and 100 beats per minute.

The first deflection of the cardiac cycle, representing atrial depolarization. Its shape and relationship to the QRS help identify the rhythm's origin.

The time from the start of the P wave to the start of the QRS complex, normally 0.12 to 0.20 second. Prolongation suggests a conduction delay.

The deflection representing ventricular depolarization, normally less than 0.12 second wide. A widened QRS suggests a ventricular origin or bundle branch block.

The time from the start of the QRS to the end of the T wave, reflecting total ventricular activity. It varies with rate and can be prolonged by certain drugs.

The flat portion between the end of the QRS and the start of the T wave. Elevation or depression here may indicate ischemia and should be reported promptly.

An ECG finding, such as marked ST elevation or a dangerous arrhythmia, that requires immediate notification of a clinician rather than routine reporting.

The documented process of notifying the responsible clinician of an abnormal or critical finding within a defined timeframe and recording who was told and when.

The written record of the procedure, including patient identifiers, date and time, lead placement, patient condition, and any problems encountered. It supports continuity and legal defensibility.

Marking each ECG with the patient's name, record number, date and time of recording, and lead or rhythm identification. Correct labels prevent misattribution and support interpretation.