CAVT 1030: Electrocardiogram Review

Vocabulary flashcards covering electrocardiography principles, lead configurations, paper measurements, anatomical landmarks, chest lead placement, lead color coding, and heart rate calculation methods.

Electrodes

Sensors that detect electrical activity of the heart.

Leads

Wires that connect electrodes to the EKG machine, identified by color and label.

Einthoven's Triangle

Anatomical triangle formed by placement of electrodes on the right arm, left arm, and left leg.

Limb Leads

EKG leads that attach to the arms and legs.

Bipolar Leads

Leads that measure electrical flow in both directions, consisting of Lead I, Lead II, and Lead III.

Lead I

Bipolar limb lead measuring electrical flow between the right arm ($RA$) and left arm ($LA$).

Lead II

Bipolar limb lead measuring electrical flow between the right arm ($RA$) and left leg ($LL$).

Lead III

Bipolar limb lead measuring electrical flow between the left arm ($LA$) and left leg ($LL$).

Unipolar Leads

Leads that measure electrical potential in one direction only.

Augmented Leads

Low voltage unipolar leads measuring electrical flow from the heart to a single limb ($aVR$, $aVL$, and $aVF$).

aVR

Augmented unipolar lead measuring electrical activity from the heart to the right arm ($RA$).

aVL

Augmented unipolar lead measuring electrical activity from the heart to the left arm ($LA$).

aVF

Augmented unipolar lead measuring electrical activity from the heart to the foot ($LL$).

Precordial Leads

Unipolar chest leads labeled $V1$ through $V6$ located on the front of the heart.

Speed Control

EKG control regulating paper/data speed, normally set at $25\,mm/sec$.

Gain

EKG control regulating the output height of the waveform, measured in millivolts ($mV$), with a normal setting of $10\,mV$.

Artifact

Unwanted signals or markings on an EKG tracing caused by non-cardiac activity such as movement, talking, or breathing.

Bradycardia

A slow heart rate below normal limits.

Tachycardia

A fast heart rate above normal limits.

EKG Paper Time Measurement

Horizontal measurement where $1$ small box = $0.04\,sec$, $1$ large box = $0.20\,sec$, and $5$ large boxes = $1\,sec$.

EKG Paper Voltage Measurement

Vertical measurement where $1$ small box = $0.1\,mV$ and $1$ large box = $0.5\,mV$.

Supine Position

Positioning a patient lying flat on their back, recommended during EKG acquisition.

Midclavicular Line

Imaginary anatomical line originating at the center of the clavicle and running down through the nipple line.

Anterior Axillary Line

Imaginary anatomical line starting at the front of the axilla and running down the left side of the chest.

Midaxillary Line

Imaginary anatomical line starting at the mid-axilla and running down the side of the chest.

Intercostal Spaces

Spaces located between the ribs, positioned directly below each corresponding rib.

V1 Placement

Chest lead placed at the fourth intercostal space, right sternal border.

V2 Placement

Chest lead placed at the fourth intercostal space, left sternal border.

V3 Placement

Chest lead placed halfway between leads $V2$ and $V4$.

V4 Placement

Chest lead placed at the fifth intercostal space at the midclavicular line.

V5 Placement

Chest lead placed at the fifth intercostal space, anterior axillary line, on the same horizontal level as $V4$.

V6 Placement

Chest lead placed at the fifth intercostal space, midaxillary line, on the same horizontal level as $V4$ and $V5$.

Right Arm (RA) Wire Color

White lead wire color.

Left Arm (LA) Wire Color

Black lead wire color.

Right Leg (RL) Wire Color

Green lead wire color.

Left Leg (LL) Wire Color

Red lead wire color.

Chest Leads (V1-V6) Wire Color

Brown lead wire color.

R-R Method

Heart rate calculation method dividing $300$ by the number of large boxes between two R-waves; least accurate approximation for regular rhythms.

1500 Method

Heart rate calculation method dividing $1500$ by the number of small boxes between R-waves; most accurate method for regular rhythms.

6-Second Method

Heart rate calculation method multiplying the number of complete complexes in a $6$-second strip ($30$ large boxes) by $10$; useful for irregular rhythms.

Serial EKGs

Multiple, consecutive EKG tracings requested over time, requiring electrodes to remain in place on the patient.