EKG Chapter 9 Vocab

escape beat

a heartbeat created when a part of the heart’s electrical conduction system other than the SA node initiates the electrical impulse that causes the heart to beat

escape rhythm

a rhythm in which a part of the heart’s electrical conduction system other than the SA node initiates all electrical impulses that cause the heart to beat (i.e., acts as the heart’s primary pacemaker)

ectopic focus

a situation in which an irritable area in the cardiac conduction system begins to generate an impulse even though the SA node may be working normally

dysrhythmia

difficult or abnormal heart rhythm; includes rhythms that are too fast, too slow, or originate in an area of the heart other than the SA node; sometimes commonly called arrhythmia

sinus rhythm

a cardiac rhythm originating in the sinus (SA) node

atrial rhythm

a cardiac rhythm originating in the atria instead of the SA node

junctional rhythm

a cardiac rhythm originating in the cells near the bundle of His or in the area of the
AV junction rather than in the SA node

ventricular rhythm

a cardiac rhythm originating in the ventricles rather than in the SA node; marked on
an EKG tracing by a widened QRS complex

heart block

a type of cardiac rhythm caused when the AV node or AV bundle delays the electrical
impulse from the SA node too long; also called AV block

underlying rhythm

the basic rhythm of a patient’s heart, separate from any abnormal beats or
complexes

sinus tachycardia

a fast sinus rhythm with normal characteristics but with a rate of 100–160 BPM

sinus bradycardia

a slow sinus rhythm with normal characteristics but with a rate below 60 BPM

sinus arrhythmia

a sinus rhythm in which all characteristics are normal except for rhythm regularity; R-
R intervals are irregular and usually vary with the patient’s breathing

sinus arrest

a sinus rhythm resulting when the SA node does not initiate an impulse, causing
pauses in the heart’s electrical activity; similar to sinoatrial block but with a greater
time between complexes. Also called sinus pause

symptomatic

experiencing symptoms

asymptomatic

not experiencing symptoms

premature atrial complex

an atrial rhythm featuring obvious premature beats; other aspects of the rhythm are
often normal

wandering atrial pacemaker

an atrial rhythm that occurs when impulses arise from multiple areas, including the
atria, the AV node, and the SA node; also called multiformed atrial rhythm

atrial tachycardia

a fast atrial rhythm caused by irritability in the atria, with a rate of 160–250 BPM

multifocal atrial tachycardia

a rhythm related to wandering atrial pacemaker, but with a ventricular rate greater
than 100 BPM

supraventricular tachycardia

can be a general term for all tachycardias (fast rhythms) that begin with impulses
generated above the ventricles, or for a specific dysrhythmia marked by a very fast
rate, P waves that are difficult or impossible to distinguish, and narrow QRS
complexes; also called narrow complex tachycardia

atrial fibrillation

a common dysrhythmia that occurs when multiple irritable sites fire in the atria;
considered controlled if the ventricular rate is under 100 BPM and uncontrolled if the
ventricular rate is above 100 BPM

rapid ventricular response

contractions of the ventricles in an atrial fibrillation rhythm at a rate of 100 BPM or
greater

atrial flutter

an atrial rhythm that occurs when an irritable site in the atria fires at a very rapid rate

F waves

short for flutter waves; waves displayed on the EKG tracing of a patient with atrial
flutter representing the distortion of the P wave as the AV node blocks impulses that
exceed 180 per minute; also called sawtooth or picket fence waves

atrial rate

the rate at which the atria contract (in normal rhythms, it is the same as the
ventricular rate)

ventricular rate

the rate at which the ventricles are contracting; in normal rhythm it is the same as the
atrial rate

vagal maneuvers

actions taken to stimulate the vagal nerve and slow the heart rate; may be
recommended by a doctor to stop certain dysrhythmias

transient rhythm

a rhythm that comes and goes

sustained rhythm

a rhythm that is always present

retrograde

moving backward; in cardiology, an impulse that travels backward compared to the
usual cardiac conduction path

premature junctional complex (PJC)

a cardiac rhythm in which an early impulse is generated by an irritable area of the AV
junction; characterized by an abnormal P wave

junctional escape beats

a cardiac rhythm in which the AV junction area generates an impulse because the SA
node is either slow to generate an impulse or does not generate one at all; as in
premature junctional complexes, the P wave is abnormal, but these beats are late
while PJCs are early

junctional escape rhythm

a cardiac rhythm created by a series of junctional escape beats; rate is usually 40–60
BPM

accelerated junctional rhythm

a cardiac rhythm with a rate of 60–100 BPM; this rhythm has a higher rate than what
is usually associated with rates generated by junctional tissue and the increased rate
represents the body’s attempt to compensate for the lack of atrial contractions

atrial kick

a common term used to describe the force of atrial contractions

junctional tachycardia

a junctional cardiac rhythm with a rate above 100 BPM

premature ventricular complex (PVC)

premature beat originating in the ventricles

bizarre

in EKG interpretation, a word used to describe a wave or complex with an abnormal
appearance

bigeminy

a word used to describe premature ventricular complexes that occur every other beat

trigeminy

a word used to describe premature ventricular complexes that occur every third beat

unifocal

in electrocardiography, originating from a single irritable site in the heart’s conduction
system, as in unifocal premature ventricular contractions

multifocal

in electrocardiography, originating from multiple irritable sites in the heart’s
conduction system, as in multifocal premature ventricular contractions

ventricular escape beats

a type of escape beat that occurs when the SA node and other potential pacemakers
above the bundle branches fail to initiate an impulse

idioventricular rhythm

a potentially lethal ventricular rhythm consisting of three or more ventricular escape
beats in a row, with a rate of 20–40 BPM; also known as ventricular escape rhythm.
Related to agonal rhythm (see separate entry)

agonal rhythm

a variation of idioventricular rhythm with a rate of 20 BPM or less. Requires
immediate intervention to prevent death

accelerated idioventricular rhythm (AIVR)

a faster ventricular rhythm consisting of three or more ventricular escape beats, with
a rate of 40–100 BPM

ventricular tachycardia

a ventricular rhythm consisting of three or more premature ventricular complexes in a
row; can be very dangerous if it lasts for more than a minute

monomorphic

in EKG interpretation, a word used to describe identical EKG features (e.g.,
premature ventricular complexes that look the same each time they occur)

polymorphic

in EKG interpretation, a word used to describe EKG features that correspond to the same thing but have differing appearances (e.g., premature ventricular complexes that look different each time they occur); also called multifocal

torsades de pointes

a variation of polymorphic ventricular tachycardia in which the QRS complex seems to “twist” from one side of the isoelectric line to the other

bundle branch block

a slowing down of the electrical impulse within the ventricles, either in the left or right bundle branches, which causes the ventricles to depolarize one after another, rather than at the same time

aberrant

in reference to the cardiac conduction system, an adjective used to describe a path of electrical impulses that differs from the normal path

ventricular fibrillation

a ventricular rhythm in which multiple sites in the ventricles are firing at a very fast rate. There is no organization to the impulses and therefore no organized contraction of the heart muscle; considered a lethal dysrhythmia and requires immediate intervention with a defibrillator; also called VF or V-fib

R-on-T phenomenon

a situation in which the QRS complex of a premature ventricular complex falls on the T wave of the previous beat; may lead to ventricular tachycardia or ventricular fibrillation

asystole

a rhythm in which there are no contractions and no cardiac activity; also sometimes called flatline

pulseless electrical activity

a situation in which a patient shows organized electrical activity but does not have a pulse; considered a lethal rhythm and requires prompt CPR and notification of the doctor

defibrillation

delivery of a shock to a patient’s heart with the goal of stopping a dangerous cardiac
rhythm and restoring a healthy rhythm

automated external defibrillator (AED)

a device attached to a patient to analyze heart rhythm and deliver a shock, if needed,
to restore a normal heart rhythm

conducted beat

a heartbeat in which the electrical impulse that begins in the SA node continues
through to the cardiac conduction system to the ventricles

blocked beat

a heartbeat in which the electrical impulse that begins in the SA node is prevented
from continuing through to the cardiac conduction system to the ventricles

first-degree heart block

a heart block rhythm marked by a PR interval greater than 0.20 seconds

second-degree heart block Mobitz type I

a heart block rhythm in which the PR intervals of conducted beats get longer and
longer until a beat is totally blocked, and then the pattern resumes; also called Wenckebach

second-degree heart block Mobitz type II

a heart block rhythm in which there is usually a fixed number of blocked P waves for
every conducted beat; the relationship between P waves and QRS complexes is
expressed as a ratio (e.g., 2:1, 3:1)

third-degree heart block

a potentially lethal heart block rhythm in which all impulses from the SA node are
blocked; there is no relationship between the activity of the atria and the activity of
the ventricles and cardiac output is severely compromised

escape pacemaker

in the cardiac conduction system, a natural pacemaker below the SA node that takes
over generating electrical impulses when the SA node fails to generate them or when
impulses from the SA node are blocked

single-chamber pacemaker

an artificial pacemaker that stimulates one area of the heart, either the atria or the
ventricles

dual-chamber pacemaker

an artificial pacemaker that stimulates both the atria and the ventricles

fixed-rate pacemaker

an artificial pacemaker that delivers stimulation consistently

failure to sense

a situation in which an artificial pacemaker does not appropriately sense the heart’s
electrical activity and does not create electrical stimulation when it should; also called
failure to pace or failure to fire

failure to capture

a situation in which the electrical stimulation generated by an artificial pacemaker
does not result in contraction of the heart muscle

ST segment depression

an abnormal EKG feature in which the ST segment is at least one millimeter (one
small block) below the isoelectric line; can be associated with ischemia

T wave inversion

a situation in which the T wave deflects downward from the isoelectric line rather than
upward; can be associated with ischemia, especially when paired with ST segment
depression

contiguous leads

in electrocardiography, two or more leads that record activity in the same area of the
heart

ST segment elevation myocardial infarction (STEMI)

a type of heart attack marked on an EKG tracing by an ST segment elevated at least
one millimeter (one small block) above the isoelectric line

cardiac catheterization

a procedure that involves inserting a tube into a blood vessel and into the heart for
testing or treatment of heart conditions

non-ST segment elevation myocardial infarction (NSTEMI)

a heart attack that does not show elevation of the ST segment on an EKG tracing