Heart Dysrhythmia

Question 1

Atrial Dysrhythmia ⤷ premature atrial complex

Answer 1

Rhythm ⤷ P-P and R-R are constant except early complexes

Rate ⤷ atria and ventricles are within normal limits of 60 to 100 bpm

P wave ⤷ early complex has a different shape being flattened, notched, or bi-phasic

PR interval ⤷ normal limits of 0.12 to 0.20 second with the early complex being different

QRS duration ⤷ normal limits of 0.06 to 0.10 second

Interpret ⤷ occurs too soon and has a positively deflected P wave that is likely to change morphology

Question 2

Atrial Dysrhythmia ⤷ wandering atrial pacemaker

Answer 2

Rhythm ⤷ slightly irregular

Rate ⤷ within normal limits of 60 to 100 bpm

P wave ⤷ continuous change in appearance with three different P waves

PR interval ⤷ varies

QRS duration ⤷ normal limits of 0.06 to 0.10 second

Interpret ⤷ changing P wave morphology with at least three variations

Question 3

Atrial Dysrhythmia ⤷ atrial flutter

Answer 3

Rhythm ⤷ R-R usually regular but may be irregular depending on AV node to limit impulses to the ventricles

Rate ⤷ atrial rate is between 250 to 350 bpm

P wave ⤷ P waves are not seen only the flutter waves are present resembling a “picket fence” in leads II, III, and aVF

PR interval ⤷ cannot be measured

QRS duration ⤷ normal limits of 0.06 to 0.10 second

Interpret ⤷ “saw-tooth” atrial pattern between QRS complexes

Question 4

Atrial Dysrhythmia ⤷ multi-focal atrial tachycardia

Answer 4

Rhythm ⤷ irregular

Rate ⤷ between 101 and 150 bpm

P wave ⤷ changes in appearance from beat to beat

PR interval ⤷ varies due to changing origin of electrical activity

QRS duration ⤷ normal limits of 0.06 to 0.10 second with all complexes looking alike

Interpret ⤷ clearly changing P wave and a heart rate of 101 to 150 bpm

Question 5

Atrial Dysrhythmia ⤷ atrial fibrillation

Answer 5

Rhythm ⤷ P-P cannot be measured because of the fibrillation while R-R is irregular

Rate ⤷ atrial rate cannot be determined while the electrical impulse ranges from 375 to 700 bpm

P wave ⤷ are not present

PR interval ⤷ not identifiable

QRS duration ⤷ normal limits of 0.06 to 0.10 second

Interpret ⤷ shows chaotic atrial electrical activity with irregular R-R intervals

Question 6

Junctional Dysrhythmia ⤷ premature junctional complex

Answer 6

Rhythm ⤷ occasionally irregular depending on the underlying rhythm

Rate ⤷ depends on the underlying rhythm

P wave ⤷ inverted and immediately precedes the QRS complex

PR interval ⤷ may be shorter if the P wave precedes the QRS complex or buried within the QRS complex

QRS duration ⤷ normal limits of 0.06 to 0.10 second

Interpret ⤷ P wave may appear before, during, or after the QRS complex

Question 7

Junctional Dysrhythmia ⤷ accelerated junctional rhythm

Answer 7

Rhythm ⤷ P-P and R-R intervals are regular and occur at similar intervals but the P interval may be difficult to measure due to the location of the P wave

Rate ⤷ ventricular rate is between 60 to 100 bpm and the atrial rate is between 60 to 100 bpm if the P wave is measurable

P wave ⤷ if seen will be inverted and may precede, follow, or fall within the QRS complex

PR interval ⤷ if P wave is seen before QRS complex the PR interval measures less than 0.12 second and is constant

QRS duration ⤷ normal limits of 0.06 to 0.10 second

Interpret ⤷ may have an inverted or absent P wave or a P wave that follows the QRS complex

Question 8

Junctional Dysrhythmia ⤷ junctional escape rhythm

Answer 8

Rhythm ⤷ P-P and R-R intervals are regular and occur at similar intervals but the P wave might be difficult to measure

Rate ⤷ ventricular and atrial rate is 40 to 60 bpm but may not be measurable if the P wave is not identifiable

P wave ⤷ usually inverted and may precede, follow, or fall within the QRS complex

PR interval ⤷ if the P wave is before the QRS complex the PR interval measures less than 0.12 second and is constant but if it was not before the interval cannot be determined

QRS duration ⤷ normal limits of 0.06 to 0.10 second

Interpret ⤷ P wave may occur before, during, or after QRS with the P wave if seen is inverted

Question 9

Junctional Dysrhythmia ⤷ junctional tachycardia

Answer 9

Rhythm ⤷ P-P and R-R intervals are regular and occur at similar intervals but the P-P interval may be difficult to measure due to the combination of the location of the P wave

Rate ⤷ ventricular and atrial rates are between 100 to 180 bpm but atrial rate may not be measurable if P waves are not identifiable

P wave ⤷ if seen will be inverted and may precede, follow, or fall within the QRS complex

PR interval ⤷ if the P wave is before the QRS complex the PR interval measures less than 0.12 second and is constant

QRS duration ⤷ normal limits of 0.06 to 0.10 second

Interpret ⤷ may be inverted or absent P wave that follows the QRS complex with a rate of 100 to 180 bpm

Question 10

Junctional Dysrhythmia ⤷ supra-ventricular tachycardia

Answer 10

Rhythm ⤷ R-R rhythm is usually regular but the atrial rhythm may or may not be seen because of other electrical activity occurring at the same time

Rate ⤷ ventricular rate is between 150 to 250 bpm but the atrial rate is difficult to determine when P waves are unidentifiable

P wave ⤷ usually not identified when the heart rate is this rapid and if present may occur simultaneously with the T wave

PR interval ⤷ cannot be determined

QRS duration ⤷ QRS measurement will be 0.12 second or greater with a delta wave

Interpret ⤷ describes a group of dysrhythmias that present with a normal-to-narrow appearing QRS complex and a greater 150 bpm

Question 11

Heart Block Dysrhythmia ⤷ first-degree atrioventricular block

Answer 11

Rhythm ⤷ regularity between the P-P and R-R interval is constant

Rate ⤷ atria and ventricles are within normal limits of 60 to 100 bpm

P wave ⤷ the same morphology with each QRS complex has a P wave before it

PR interval ⤷ greater than 0.20 second

QRS duration ⤷ normal limits of 0.06 to 0.10 second

Interpret ⤷ PR interval is constant and measures greater than 0.20 second

Question 12

Heart Block Dysrhythmia ⤷ second degree atrioventricular block type I

Answer 12

Rhythm ⤷ P-P interval is regular while the R-R interval is irregular

Rate ⤷ atrial rate is within normal limits but the ventricular rate is slower

P wave ⤷ normal size with an upright P wave with an extra P wave with every QRS complex

PR interval ⤷ varies from one measurement to the next becoming progressively longer with each subsequent conducted P wave until the QRS complex is blocked

QRS duration ⤷ normal limits of 0.06 to 0.10 second

Interpret ⤷ has a cycling prolonging PR interval until the QRS is blocked then the cycle resets

Question 13

Heart Block Dysrhythmia ⤷ second degree atrioventricular block type II

Answer 13

Rhythm ⤷ P-P interval is regular but the R-R interval may or may not be regular due to the unpredictable nature of the blocked impulses

Rate ⤷ atrial rate is within normal limits while the ventricular rate is slower

P wave ⤷ morphology will be normal with an upright waves and at least one P wave for every QRS complex

PR interval ⤷ constant and remains constant even after QRS drop occurs

QRS duration ⤷ normal limits of 0.06 to 0.10 second

Interpret ⤷ QRS complexes are missing but wherever a P is with the QRS complex the PR interval measures the same

Question 14

Heart Block Dysrhythmia ⤷ third degree atrioventricular block

Answer 14

Rhythm ⤷ P-P interval and R-R are regular but their intervals are different

Rate ⤷ atrial rate is within normal limits but the ventricular rate is slow between 20 to 40 bpm or 40 to 60 bpm

P wave ⤷ normal size but the location may be buried within the QRS complex therefor having no correlation between the P waves and QRS complex

PR interval ⤷ variable due to the atrial and ventricular depolarizing at different rates

QRS duration ⤷ duration and morphology are at the same but the measurements may be within normal limits or wide

Interpret ⤷ the P-P and R-R intervals are regular but the atria and ventricles are firing at different rates with this being the only block in which P waves are buried inside a QRS complex

Question 15

Ventricular Dysrhythmia ⤷ premature ventricular complexes

Answer 15

Rhythm ⤷ P-P intervals are regular and the R-R intervals are regular with the exception of the early complexes from the PVCs but there may be a compensatory pause

Rate ⤷ influenced by the number of ectopic complexes present so the six-second method must be used

P wave ⤷ not present for the early ventricular complexes

PR interval ⤷ early complex no P wave is present

QRS duration ⤷ must be analyzed for both the underlying rhythm and the premature complexes measuring 0.12 second or greater

Interpret ⤷ early QRS complex that measures 0.12 second or greater and has a bizarre, wide appearance with no P wave

Question 16

Uni-focal PVC

Answer 16

All complexes have a similar shape, suggesting only one irritable focus

Question 17

Multi-focal PVC

Answer 17

PVCs have varied shapes and forms, suggesting more than one irritable focus

Question 18

Interpolated PVC

Answer 18

PVC occurs during the normal R-R interval without interrupting the underlying rhythm

Question 19

Occasional PVC

Answer 19

Less than six PVCs per minute

Question 20

Frequent PVC

Answer 20

Six or more PVCs per minute

Question 21

Trigeminy

Answer 21

Every third complex is a PVC

Question 22

Quadgeminy

Answer 22

Every fourth complex is a PVC

Question 23

R-on-T PVC

Answer 23

PVC occurs on the down-slope of the T wave which signifies the vulnerable period of the relative ventricular refractory period

Question 24

Coupling

Answer 24

Two PVCs that occur back to back

Question 25

Run of ventricular tachycardia

Answer 25

Three or more PVCs in a row at a rate greater than 100 bpm (known as triplet PVCs or salvo)

Question 26

Paroxysmal event

Answer 26

Change from sinus rhythm to SVT showing a change from ventricular tachycardia to ventricular fibrillation

Question 27

Ventricular Dysrhythmia ⤷ agonal rhythm

Answer 27

Rhythm ⤷ R-R interval may or may not be regular but there are no P-P intervals Rate ⤷ atrial rate cannot be determined due to the absence of atrial depolarization but the ventricular rate is less than 20 bpm P wave ⤷ no analysis PR interval ⤷ cannot be measured QRS duration ⤷ measure 0.12 second or greater and have a wide, bizarre appearance Interpret ⤷ absence of P waves and ventricular rate of less than 20 bpm with wide and bizarre QRS complexes

Question 28

Ventricular Dysrhythmia ⤷ idioventricular rhythm

Answer 28

Rhythm ⤷ P-P cannot be determined but the R-R is regular Rate ⤷ cannot be determined due to the absence of atrial depolarization while the ventricular rate is a slow 20 to 40 bpm P wave ⤷ usually absent PR interval ⤷ cannot be measured QRS duration ⤷ measures 0.12 second or greater and the QRS complex has a wide, bizarre appearance Interpret ⤷ an absence of P waves, a slow ventricular rate of 20 to 40 bpm, and wide and bizarre QRS complexes

Question 29

Ventricular Dysrhythmia ⤷ accelerated idioventricular rhythm

Answer 29

Rhythm ⤷ P-P cannot be determined but the R-R is regular Rate ⤷ cannot be determined due to the absence of atrial depolarization while the ventricular rate is a slow 40 to 100 bpm P wave ⤷ usually absent PR interval ⤷ cannot be measured QRS duration ⤷ measures 0.12 second or greater and the QRS complex has a wide, bizarre appearance Interpret ⤷ absence of P waves, a ventricular rate of 40 to 100 bpm, and wide and bizarre QRS complexes

Question 30

Ventricular Dysrhythmia ⤷ ventricular tachycardia

Answer 30

Rhythm ⤷ P-P interval is usually not identifiable while the R-R is usually regular but may be slightly irregular at times Rate ⤷ atrial rate cannot be determined because the P-P interval cannot be recognized but the atrial rate is fast and between 100 to 200 bpm P wave ⤷ absent PR interval ⤷ cannot be measured QRS duration ⤷ measure 0.12 second or greater and have a wide and bizarre appearance with an increase in amplitude with the T wave in the opposite direction Interpret ⤷ wide and bizarre QRS complexes with a "sawtooth" appearance and an excess rate of 100 bpm with no P wave

Question 31

Ventricular Dysrhythmia ⤷ ventricular fibrillation

Answer 31

Rhythm ⤷ cannot be determined because neither P nor R waves are present on strips Rate ⤷ atrial and ventricular rates cannot be identified because neither the atria nor ventricles are full depolarizing P wave ⤷ no P waves PR interval ⤷ no interval QRS duration ⤷ cannot be measured because only fibrillatory waves are present Interpret ⤷ absence of organized electrical activity

Question 32

Ventricular Dysrhythmia ⤷ asystole

Answer 32

Rhythm ⤷ no wave-forms Rate ⤷ no rates present P wave ⤷ no waves present PR interval ⤷ cannot be measured QRS duration ⤷ cannot be measured Interpret ⤷ flat-line

Question 33

Bundle Branch Block Dysrhythmia ⤷ left bundle branch block

Answer 33

Rhythm ⤷ depends on the underlying rhythm with the possibility of both being regular or irregular Rate ⤷ atrial and ventricular rates depend on the basic rhythm P wave ⤷ depend on the basic rhythm PR interval ⤷ normal measurement of 0.12 to 0.20 second QRS duration ⤷ 0.12 second or greater in length with the widening of the QRS duration indicating the presence of a block Interpret ⤷ j-point is deflected down

Question 34

Complication of pacemaker ⤷ malfunctioning

Answer 34

Cause ⤷ pacemaker does not send impulse Occurs ⤷ intervals are irregular and the impulse is slower than the set rate Symptom ⤷ may experience hypo-tension, light headed, and black-out periods

Question 35

Pacemaker complication ⤷ failure to sense

Answer 35

Cause ⤷ pacemaker does not send electrical impulse to the myocardium Occurs ⤷ may send current to heart during relaxation phase Symptoms ⤷ atrial fibrillation can occur along with ventricular pacing, ventricular tachycardia, or ventricular fibrillation

Question 35

Pacemaker complication ⤷ loss of capture

Answer 35

Cause ⤷ pacing activity occurs but the myocardium is not depolarized Occurs ⤷ pacing spikes will occur without capture of a wave form Symptoms - depends on the basic dysrhythmia and the patients condition

Question 36

Pacemaker complication ⤷ over-sensing

Answer 36

Cause ⤷ perceives electrical current from sources other than the heart Occurs ⤷ patients own heart rate is recorded and is slower than the pacemaker or the pacemaker spikes Symptoms ⤷ signs of low cardiac output

Question 37

Pacemaker complication ⤷ under-sensing

Answer 37

Cause ⤷ pacemaker is unable to detect any activity Occurs ⤷ never turns off resulting in competition between intrinsic and electronic pacemakers Symptoms ⤷ signs of low cardiac output depending of the severity of the rhythm