CARD 120 Exam 2

SUPRAVENTRICULAR TACHYCARDIA

Sinus Tachycardia 100-160 bpm Atrial Tachycardia 150-250 bpm Atrial Flutter 150-250 bpm Junctional Tachycardia 100-180 bpm

PREMATURE ATRIAL COMPLEX

Pacemaker: an irritable focus within the atrium Rate: depends on underlying rhythm Regularity: the ectopic interrupts the regularity of the underlying rhythm P Wave: P wave of early beat differs from the sinus P waves; can be flattened or notched; may be lost in the preceding T wave PRI: 0.12-0.20 second; can exceed 0.20 second QRS: less than 0.12 second

WANDERING PACEMAKER

Pacemaker: wanders between SA node, atria, and AV junction Conduction is normal each impulse is conducted through to the ventricles Regularity: slightly irregular Rate: usually normal, 60-100 bpm P Wave: morphology changes from one complex to the next PRI: less than 0.20 second; may vary QRS: less than 0.12 second

Unifocal PVC

PVC's that all originate from a single ventricular focus and thus have similar configurations.

Multifocal PVC's

PVC's that arise from many foci and assume a variety of configurations.

Junctional Tachycardia

Pacemaker: AV junction Conduction speeds up to override higher sites Rate: 100-180 bpm Regularity: regular P Wave: will be inverted; can fall before or after the QRS complex or can be hidden within the QRS complex PRI: can be measured only if the P wave precedes the QRS complex; if measurable, will be less than 0.12 second QRS: less than 0.12 second

JUNCTIONAL TACHYCARDIA

Pacemaker: AV junction Conduction speeds up to override higher sites Rate: 60-100 bpm Regularity: regular PRI: can be measured only if the P wave precedes the QRS complex; if measurable, will be less than 0.12 second QRS: less than 0.12 second

SINUS ARRHYTHMIA

Pacemaker: Sinus Node Rate: 60-100 bpm Regularity: irregular Rate: 60-100 bpm (usually) P Wave: uniform shape; one P wave in front of every QRS complex PRI: 0.12-0.20 second and constant QRS: less than 0.12 second

Normal Sinus Rhythm (NSR)

Pacemaker: Sinus Node Rate: 60-100 bpm Regularity: regular Rate: 60-100 bpm P Wave: uniform shape; one P wave in front of every QRS complex PRI: 0.12-0.20 second and constant QRS: less than 0.12 second

SINUS BRADYCARDIA

Pacemaker: Sinus Node Rate: <60 bpm Regularity: regular Rate: less than 60 bpm P Wave: uniform shape; one P wave in front of every QRS complex PRI: 0.12-0.20 second and constant QRS: less than 0.12 second

SINUS TACHYCARDIA

Pacemaker: Sinus Node Rate: >100 bpm Regularity: regular Rate: greater than 100 bpm (usually does not exceed 160 bpm) P Wave: uniform shape; one P wave in front of every QRS complex PRI: 0.12-0.20 second and constant QRS: less than 0.12 second

PREMATURE JUNCTIONAL COMPLEX (pjc)

Pacemaker: a single irritable focus within the AV junction Rate: depends on underlying rhythm Regularity: ectopic interrupts underlying rhythm Rate: depends on rate of underlying arrhythmia P Wave: will be inverted; can fall before, during, or after the QRS complex PRI: can be measured only if the P wave precedes the QRS complex; if measurable, will be less than 0.12 second QRS: less than 0.12 second

ATRIAL TACHYCARDIA

Pacemaker: a single irritable focus within the atrium Rate: 150-250 bpm Conduction: normal Regularity: regular Rate: 150-250 bpm P Wave: atrial P wave; differs from sinus P wave; can be lost in T wave PRI: 0.12-0.20 second QRS: less than 0.12 second

A PVC is

a single ectopic beat arising from an irritable focus in the ventricles. It comes earlier than expected and interrupts the regularity of the underlying rhythm

Supraventricular Tachycardia

If a rapid arrhythmia is regular, has no visible P waves, and has a rate range common to other arrhythmias, thereby making more accurate identification impossible

All ventricular impulses will have a QRS measurement of

0.12 second or greater.

Sinus Tachycardia

100-160 bpm

Junctional Tachycardia (jt)

100-180 bpm

Junctional Tachycardia Rate

100-180 bpm

Atrial Flutter

150-250 bpm

Atrial Tachycardia

150-250 bpm

Regularity: Regular PRI Measurement: Consistent (Greater than .20) No Extra P Waves

1st Degree Type One

Regularity: depends on underlying rhythm Rate: depends on underlying rhythm P Waves: upright and uniform; each P wave will be followed by a QRS complex PRI: greater than 0.20 second; constant across the strip QRS: less than 0.12 second

1st degree block

Regularity: Irregular PRI Measurement: Irregular/Inconsistent Extra P Waves

2nd Degree Type 1 (Wenckebach)

Regularity: Irregular or Regular PRI Measurement: Regular/Consistent Extra P Waves

2nd Degree Type 2

Regularity: irregular in a pattern of grouped beating Rate: usually slightly slower than normal P Waves: upright and uniform; some P waves are not followed by QRS complexes PRI: progressively lengthens until one P wave is blocked QRS: less than 0.12 second

2nd degree block type 1

Regularity: R-R interval can be regular or irregular; P-P interval is regular Rate: usually in the bradycardia range (< 60 bpm); can be onehalf to one-third the normal rate P Waves: upright and uniform; more than one P wave for every QRS complex PRI: always constant across the strip; can be greater than 0.20 second QRS: less than 0.12 second

2nd degree block type 2

Regularity: regular Rate: AR—usually normal (60-100 bpm); VR—40-60 if focus is junctional; 20-40 if focus is ventricular P Waves: upright and uniform; more P waves than QRS complexes PRI: no relationship between P waves and QRS complexes; P waves can occasionally be found superimposed on the QRS complex QRS: less than 0.12 second if focus is junctional; 0.12 second or greater if focus is ventricular

3rd degree heart block

Junctional Escape Rhythm

40-60 bpm

The normal inherent rate of the AV junction is

40-60 bpm

Junctional Tachycardia is usually divided into two categories, depending on rate:

60-100 beats Accelerated Junctional 100-180 beats Junctional Tachycardia

Accelerated Junctional Rhythm

60-100 bpm

Interpolated PVC

A PVC between two sinus beats without interrupting the underlying rhythm.

"R on T" phenomenon

A PVC that lands during the vulnerable (relative refractory) phase of the cardiac cycle it can produce a lethal, repetitive arrhythmia.

UNIFOCAL

Arising from a single site

Patterns of Grouped Beating:

Bigeminy Trigeminy Quadrigeminy

Mechanism of Third-Degree Heart Block (CHB)

Complete Heart Block - Pacemaker: SA node is firing, but an escape pacemaker below the block is controlling the heart. - Rate: atrial rate is normal, but ventricular rate is slower than normal. - Regularity: atria regular, ventricles regular. Conduction: no sinus impulse gets through the AV node, if a junctional focus is in control, conduction though the ventricles is normal; if ventricular pacemaker is in control, conduction is delayed.

Mechanism of First-Degree Heart Block

Delay in AV node - Pacemaker: SA node - Rate: depends on underlying rhythm - Regularity: depends on underlying rhythm Conduction: AV node holds each sinus impulse longer than normal, but eventually allows each impulse to proceed normally through to the ventricles.

Junctional Escape Rhythm

If higher pacemaker sites fail, a junctional escape pacemaker might take over control of the heart

Junctional Tachycardia

If the AV junction becomes irritable, it can speed up and override higher pacemaker sites.

INVERTED P WAVE (hidden)

If the atria and the ventricles are depolarized simultaneously, there will be no visible P wave, since it is hidden within the QRS complex.

Mechanism of Second-Degree Heart Block Type II

Intermittent block - Pacemaker: SA Node - Rate: atrial rate normal; ventricular rate is slow, usually 1/2 to 1/3 atrial rate. - Regularity: depends on conduction ratio; regular if ratio is consistent, irregular if ratio varies Conduction: AV node selectively allows some impulses through while blocking others. rise that get through the AV node proceed normally through the ventricles.

Does NSR CAUSE TROUBLE FOR THE PATEINT?

NO

Rhythms that originate in the AV junction include:

Premature Junctional Complex Junctional Escape Rhythm Accelerated Junctional Rhythm Junctional Tachycardia

PREMATURE VENTRICULAR COMPLEX

REGULARITY: The underlying rhythm can be regular or irregular. They will interrupt the regularity of the underlying rhythm (unless the PVC is interpolated). ectopic PVC RATE: The rate will be determined by the underlying rhythm. PVCs are not usually included in the rate determination because they frequently do not produce a pulse. P WAVE: The ectopic is not preceded by a P wave. You may see a coincidental P wave near the PVC, but it is dissociated. PRI: Since the ectopic comes from a lower focus, there will be no PRI. QRS: The QRS complex will be wide and bizarre, measuring at least 0.12 sec. The configuration will differ from the configuration of the underlying QRS complexes. The T wave is frequently in the opposite direction from the QRS complex.

DOES A WONDERING PACEMAKER CAUSE SYMPTOMS FOR THE PATEINT?

Rarely (it is benign)

DOES SINUS ARRHYTHMIA CAUSE TROBLE FOR THE PATEINT?

Rarely (it is benign)

The rules for Asystole are:

Regularity: Rate: P Waves: straight line indicates absence of electrical activity PRI: QRS:

The rules for Ventricular Fibrillation are:

Regularity: Rate: P Waves: totally chaotic with no discernible waves or complexes PRI: QRS:

The rules for Premature Ventricular Complexes are

Regularity: ectopics will disrupt regularity of underlying rhythm Rate: depends on underlying rhythm and number of ectopics P Waves: will not be preceded by a P wave; dissociated P waves may be seen near PVC PRI: since the ectopic comes from a lower focus, there will be no PRI QRS: wide and bizarre; 0.12 second or greater; T wave is usually in opposite direction from R wave.

The rules for Idioventricular Rhythm are:

Regularity: usually regular (it can be unreliable since it is such a low site) Rate: 20-40 bpm; can drop below 20 bpm P Waves: none PRI: none QRS: wide and bizarre; 0.12 second or greater

The rules for Ventricular Tachycardia are:

Regularity: usually regular; can be slightly irregular Rate: 150-250 bpm; can exceed 250 bpm if the rhythm progresses to Ventricular Flutter; may occasionally be slower than 150 bpm, in which case it is called a slow VT P Waves: will not be preceded by P waves; dissociated P waves may be seen PRI: since the focus is in the ventricles, there will be no PRI QRS: wide and bizarre; 0.12 second or greater; T wave is usually in opposite direction from R wave

Ventricular arrhythmias are the most serious arrhythmias because

because the heart is less effective than usual and because the heart is functioning on its last level of backup support.

THIRD-DEGREE HEART BLOCK

Regularity: Both atrial and ventricular foci are firing regularly; thus the P-P intervals and the R-R intervals are regular. Rate: The atrial rate will usually be in a normal range. The ventricular rate will be slower. If a junctional focus is controlling the ventricles, the rate will be 40-60 bpm. If the focus is ventricular, the rate will be 20-40 bpm. P Wave: The P waves are upright and uniform. There are more P waves than QRS complexes. PRI: Since the block at the AV node is complete, none of the atrial impulses is conducted through to the ventricles. There is no PRI. The P waves have no relationship to the QRS complexes. You may occasionally see a P wave superimposed on the QRS complex. QRS: If the ventricles are being controlled by a junctional focus, the QRS complex will measure less than 0.12 sec. If the focus is ventricular, the QRS will measure 0.12 sec or greater.

Rules for First-Degree Heart Block

Regularity: Depends on underlying Rhythm Rate: Depends on underlying rhythm P Wave: Upright and uniform; each P wave will be followed by a QRS complex. PRI: Greater than 0.20 seconds; constant across strip QRS: Less than 0.12 second

SECOND-DEGREE HEART BLOCK Type 2

Regularity: If the conduction ratio is constant, the R-R interval will be constant, and the rhythm will be regular. If the conduction ratio varies, the R-R will be irregular. Rate: The atrial rate is usually normal (60-100 bpm). Since many of the atrial impulses are blocked, the ventricular rate will usually be in the bradycardia range (<60 bpm), often one half, one third, or one fourth of the atrial rate. P Wave: The P waves are upright and uniform. There are always more P waves than QRS complexes. PRI: The PRI on conducted beats will be constant across the strip, although it might be longer than a normal PRI measurement. QRS: The QRS complex measurement will be less than 0.12 sec.

Rules for Second-Degree Heart Block Type II

Regularity: Regular (atrial) and irregular (ventricular) Rate: Characterized by Atrial rate usually faster than ventricular rate (usually slow) P Wave: Normal form, but more P waves than QRS complexes. PRI: Constant across the strip. Normal or prolonged QRS: Normal or wide. less than .12 seconds

PREMATURE JUNCTIONAL COMPLEX

Regularity: Since this is a single premature ectopic beat, it will interrupt the regularity of the underlying rhythm. Rate: The overall heart rate will depend on the rate of the underlying rhythm. P Wave: The P wave can come before or after the QRS complex, or it can be lost entirely within the QRS complex. If visible, the P wave will be inverted. PRI: If the P wave precedes the QRS complex, the PRI will be less than 0.12 sec. If the P wave falls within the QRS complex or following it, there will be no PRI. QRS: The QRS complex measurement will be less than 0.12 sec.

PREMATURE ATRIALCOMPLEX

Regularity: Since this is a single premature ectopic beat, it will interrupt the regularity of the underlying rhythm. Rate: The overall heart rate will depend on the rate of the underlying rhythm. P Wave: The P wave of the premature beat will have a different morphology than the P waves of the rest of the strip. The ectopic beat will have a P wave, but it can be flattened, notched, or otherwise unusual. It may be hidden within the T wave of the preceding complex. PRI: The PRI should measure between 0.12 and 0.20 sec, but can be prolonged; the PRI of the ectopic will probably be different from the PRI measurements of the other complexes. QRS: The QRS complex measurement will be less than 0.12 sec.

FIRST DEGREE

Regularity: Since this is not a rhythm itself, but a feature superimposed on another rhythm, the regularity will depend on the regularity of the underlying rhythm. Rate: The rate will depend on the rate of the underlying rhythm. P Wave: The P waves will be upright and uniform. Each P wave will be followed by a QRS complex. PRI: The PRI will be constant across the entire strip, but it will always be greater than 0.20 sec. QRS: The QRS complex measurement will be less than 0.12 sec.

Second Degree Type 1 WENCKEBACH

Regularity: The R-R interval is irregular in a pattern of grouped beating. Rate: Since some beats are not conducted, the ventricular rate is usually slightly slower than normal (<100 bpm). The atrial rate is usually normal (60-100 bpm). P Wave: The P waves are upright and uniform. Some P waves are not followed by QRS complexes. PRI: The PR intervals get progressively longer, until one P wave is not followed by a QRS complex. After the blocked beat, the cycle starts again. QRS: The QRS measurement will be less than 0.12 sec.

ACCELERATED JUNCTIONAL RHYTHM

Regularity: The R-R intervals are constant; the rhythm is regular. Rate: Atrial and ventricular rates are equal. The rate will be faster than the AV junction's inherent rate but not yet into a true tachycardia range. It will be in the 60-100 bpm range. S complex, or it can be lost entirely within the PRI: If the P wave precedes the QRS complex, the PRI will be less than 0.12 sec. If the P wave falls within the QRS complex or following it, there will be no PRI. QRS: The QRS complex measurement will be less than 0.12 sec.

JUNCTIONAL TACHYCARDIA

Regularity: The R-R intervals are constant; the rhythm is regular. Rate: Atrial and ventricular rates are equal. The rate will be in the tachycardia range, but does not usually exceed 180 bpm. Usual rate range is 100-180 bpm P Wave: The P wave can come before or after the QRS complex, or it can be lost entirely within the QRS complex. If visible, the P wave will be inverted. PRI: If the P wave precedes the QRS complex, the PRI will be less than 0.12 sec. If the P wave falls within the QRS complex or following it, there will be no PRI. QRS: The QRS complex measurement will be less than 0.12 sec.

JUNCTIONAL ESCAPE RHYTHM

Regularity: The R-R intervals are constant; the rhythm is regular. Rate: Atrial and ventricular rates are equal; the inherent rate of the AV junction is 40-60 bpm. P Wave: The P wave can come before or after the QRS complex, or it can be lost entirely within the QRS complex. If visible, the P wave will be inverted. PRI: If the P wave precedes the QRS complex, the PRI will be less than 0.12 sec. If the P wave falls within the QRS complex or following it, there will be no PRI. QRS: The QRS complex measurement will be less than 0.12 sec.

NORMAL SINUS RHYTHM

Regularity: The R-R intervals are constant; the rhythm is regular. Rate: The atrial and ventricular rates are equal; heart rate is between 60 and 100 bpm. P Wave: The P waves are uniform. There is one P wave in front of every QRS complex. PRI: The PR Interval measures between 0.12 and 0.20 sec; the PRI measurement is constant across the strip. QRS: The QRS complex measures less than 0.12 sec

SINUS BRADYCARDIA

Regularity: The R-R intervals are constant; the rhythm is regular. Rate: The atrial and ventricular rates are equal; heart rate is less than 60 bpm. P Wave: There is a uniform P wave in front of every QRS complex. PRI: The PR interval measures between 0.12 and 0.20 sec; the PRI measurement is constant across the strip. QRS: The QRS complex measures less than 0.12 sec.

SINUS TACHYCARDIA

Regularity: The R-R intervals are constant; the rhythm is regular. Rate: The atrial and ventricular rates are equal; the heart rate is greater than 100 bpm (usually between 100 and 160 bpm). P Wave: There is a uniform P wave in front of every QRS complex. PRI: The PRI interval measures between 0.12 and 0.20 sec; the PRI measurement is constant across the strip. QRS: The QRS complex measures less than 0.12 sec.

ATRIAL TACHYCARDIA

Regularity: The R-R intervals are constant; the rhythm is regular. Rate: The atrial and ventricular rates are equal; the heart rate is usually 150-250 bpm. P Wave: There is one P wave in front of every QRS complex. The configuration of the P wave will be different than that of sinus P waves; they may be flattened or notched. Because of the rapid rate, the P waves can be hidden in the T waves of the preceding beats. PRI: The PRI is between 0.12 and 0.20 sec and constant across the strip. The PRI may be difficult to measure if the P wave is obscured by the T wave.

WANDERING PACEMAKER

Regularity: The R-R intervals vary slightly as the pacemaker site changes; the rhythm can be slightly irregular. Rate: The atrial and ventricular rates are equal; heart rate is usually with a normal range (60-100 bpm). P Wave: The morphology of the P wave changes as the pacemaker site changes. There is one P wave in front of every QRS complex, although some may be difficult to see, depending on the pacemaker site. PRI: The PRI measurement will vary slightly as the pacemaker site changes. All PRI measurements should be less than 0.20 sec; some may be less than 0.12 sec. QRS: The QRS complex measures less than 0.12 sec.

Wandering Pacemaker

Regularity: The R-R intervals vary slightly as the pacemaker site changes; the rhythm can be slightly irregular. Rate: The atrial and ventricular rates are equal; heart rate is usually with a normal range (60-100 bpm). P Wave: The morphology of the P wave changes as the pacemaker site changes. There is one P wave in front of every QRS complex, although some may be difficult to see, depending on the pacemaker site. PRI: The PRI measurement will vary slightly as the pacemaker site changes. All PRI measurements should be less than 0.20 sec; some may be less than 0.12 sec. QRS: The QRS complex measures less than 0.12 sec.

SINUS ARRHYTHMIA

Regularity: The R-R intervals vary; the rate changes with the patient's respirations. Rate: The atrial and ventricular rates are equal; heart rate is usually in a normal range (60-100 bpm), but can be slower. P Wave: There is a uniform P wave in front of every QRS complex. PRI: The PR interval measures between 0.12 and 0.20 sec; the PRI measurement is constant across the strip. QRS: The QRS complex measures less than 0.12 sec.

ATRIAL FIBRILLATION

Regularity: The atrial rhythm is not measurable; all atrial activity is chaotic. The ventricular rhythm is grossly irregular, having no pattern to its irregularity. Rate: The atrial rate cannot be measured because it is so chaotic; research indicates that it exceeds 350 bpm. The ventricular rate is significantly slower because the AV node blocks most of the impulses. If the ventricular rate is 100 bpm or less, the rhythm is said to be "controlled." If it is over 100 bpm, it is considered to have a rapid ventricular response and is called "uncontrolled." P Wave: In this arrhythmia the atria are not depolarizing in an effective way; instead, they are fibrillating. Thus, no P wave is produced. All atrial activity is depicted as "fibrillatory" waves, or grossly chaotic undulations of the baseline. PRI: Since no P waves are visible, no PRI can be measured. QRS: The QRS complex measurement should be less than 0.12 sec.

ATRIAL FLUTTER

Regularity: The atrial rhythm is regular. The ventricular rhythm will be regular if the AV node conducts impulses through in a consistent pattern. If the pattern varies, the ventricular rate will be irregular. Rate: The atrial rate is between 250 and 350 bpm. Ventricular rate will depend on the ratio of impulses conducted through to the ventricles. P Wave: When the atria flutter, they produce a series of well-defined P wave. When seen together, these "Flutter" waves have a sawtooth appearance. PRI: Because of the unusual configuration of the P wave (Flutter wave) and the proximity of the wave to the QRS complex, it is often impossible to determine the PRI in this arrhythmia. Therefore, the PRI is not measured in Atrial Flutter. QRS: The QRS complex measures less than 0.12 sec; measurement can be difficult if one or more Flutter waves is concealed within the QRS complex.

VENTRICULAR FIBRILLATION

Regularity: There are no waves or complexes that can be analyzed to determine regularity. The baseline is totally chaotic. Rate: The rate cannot be determined since there are no discernible waves or complexes to measure. P Wave: There are no discernible P waves. PRI: There is no PRI. QRS: There are no discernible QRS complexes.

ASYSTOLE

Regularity: There is no electrical activity, only a straight line. Rate: There is no electrical activity, only a straight line. P Wave: There is no electrical activity, only a straight line. PRI: There is no electrical activity, only a straight line. QRS: There is no electrical activity, only a straight line.

VENTRICULAR TACHYCARDIA

Regularity: This rhythm is usually regular, although it can be slightly irregular. Rate: Atrial rate cannot be determined. The ventricular rate range is 150-250 bpm. If the rate is below 150 bpm, it is considered a slow VT. If the rate exceeds 250 bpm, it is called Ventricular Flutter. P Wave: None of the QRS complexes will be preceded by P waves. You may see dissociated P waves intermittently across the strip. PRI: Since the rhythm originates in the ventricles, there will be no PRI. QRS: The QRS complexes will be wide and bizarre, measuring at least 0.12 sec. It is often difficult to differentiate between the QRS and the T wave.

IDIOVENTRICULAR RHYTHM

Regularity: This rhythm is usually regular, although it is less reliable as the heart dies. Rate: The ventricular rate is usually 20-40 bpm, but it can drop below 20 bpm. P Wave: There are no P waves in this arrhythmia. PRI: There is no PRI. QRS: The QRS complex is wide and bizarre, measuring at least 0.12 sec.

ATRIAL FLUTTER

Regularity: atrial rhythm is regular; ventricular rhythm is usually regular but can be irregular if there is variable block Rate: atrial rate 250-350 bpm; ventricular rate varies P Wave: characteristic sawtooth pattern PRI: unable to determine QRS: less than 0.12 second

Rules for Premature Junctional Complex:

Regularity: depends on regularity of underlying arrhythmia Rate: depends on rate of underlying arrhythmia P Waves: will be inverted; can fall before, during, or after the QRS complex PRI: can only be measured if the P wave precedes the QRS complex; if measurable, will be less than 0.12 seconds QRS: less than 0.12 seconds

ATRIAL FIBRILLATION

Regularity: grossly irregular Rate: atrial rate greater than 350 bpm; ventricular rate varies greatly P Wave: no discernible P waves; atrial activity is referred to as fibrillatory waves (f waves) PRI: unable to measure QRS: less than 0.12 second

The rules for Junctional Tachycardia are:

Regularity: regular Rate: 100-180 bpm P Waves: will be inverted; can fall before, during, or after the QRS complex PRI: can be measured only if the P wave precedes the QRS complex; if measurable, will be less than 0.12 seconds QRS: less than 0.12 seconds

The rules for Junctional Escape Rhythm:

Regularity: regular Rate: 40-60 bpm P Waves: will be inverted; can fall before, during, or after the QRS complex PRI: can be measured only if the P wave precedes the QRS complex; if measurable, will be less than 0.12 seconds QRS: less than 0.12 seconds

The rules for Accelerated Junctional Rhythm are:

Regularity: regular Rate: 60-100 bpm P Waves: will be inverted; can fall before, during, or after the QRS complex PRI: can be measured only if the P wave precedes the QRS complex; if measurable, will be less than 0.12 seconds QRS: less than 0.12 seconds

JUNCTIONAL ESCAPE RHYTHM

Regularity: regular Rate: 40-60 bpm P Wave: will be inverted: can fall before or after the QRS complex or can be hidden within the QRS complex PRI: can be measured only if the P wave precedes the QRS complex; if measurable, will be less than 0.12 second QRS: less than 0.12 second

What is the significance of Atrial Flutter?

SIGNIFICANCE: This rhythm is trouble; it can cause symptoms, but is not usually lethal. · The rapid ventricular rate and loss of atrial kick can reduce cardiac output. This rhythm produces a risk of pulmonary or cerebralemboli. · It can cause CHF or myocardial ischemia (congestive heart failure). It is seen in CAD and rheumatic heart disease (Coronary ArteryDisease).

WENCKEBACH

Second degree heart block Type 1

complete heart block

THIRD-DEGREE HEART BLOCK

following inverted p wave

The P wave will follow the QRS complex if the ventricles are depolarized before the atria

preceding inverted p wave

The P wave will precede the QRS complex if the atria are depolarized before the ventricles. In such a case, the PRI will be less than 0.12 seconds.

Regularity: Regular PRI Measurement: Irregular/Inconsistent Extra P Waves

Third Degree

what is the significance of aystole

This rhythm causes clinical death

What is the significance of Idioventricular rhythms?

This rhythm causes clinical death. · This rhythm cannot sustain perfusion. · This is not a viable rhythm; if it cannot be corrected, the patient cannot survive.

What is the significance of ventricular fibrillation

This rhythm causes clinical death. · This rhythm is indicative of extreme myocardial irritability. · This is not a viable rhythm; if it cannot be converted, the patient cannot survive.

what is the significance of a PJC?

This rhythm is a warning(; though not serious itself, it can lead to more serious arrhythmias. · It may precede AV block.)

What is the significance of Junctional Tachycardia

This rhythm is a warning(; though not serious itself, it can lead to more serious arrhythmias. · This rhythm indicates an irritable junction overriding a normal pacemaker. · It is often caused by AMI, open-heart surgery, myocarditis, or dig-toxicity.)

What is the significance of a Accelerated Junctional Rhythm

This rhythm is a warning(; though not serious itself, it can lead to more serious arrhythmias.)

what is the significance of a J.E.R?

This rhythm is a warning(; though not serious itself, it can lead to more serious arrhythmias.)

What is the significance of a PAC?

This rhythm is benign; it rarely causes symptoms (· This rhythm can be an early sign of CHF (congestive heart failure). · It can lead to atrial tachyarrhythmias. It can be caused by fatigue, hypoxia, dig-toxicity, caffeine, ischemia, CHF, or alcohol)

What is the significance of A.Fib?

This rhythm is trouble; (it can cause symptoms, but is not usually lethal. · The rapid ventricular rate and loss of atrial kick can reduce cardiac output. · This rhythm produces a risk of pulmonary or cerebral emboli. · It can cause CHF or myocardial ischemia. · It is commonly caused by dig-toxicity. · It is a common chronic rhythm in the elderly.

What is the significance of Atrial Tachycardia?

This rhythm is trouble; it can cause symptoms, but is not usually lethal. (• It is very dangerous in AMI or heart disease. • It is commonly caused by dig-toxicity.)

Mechanism of Second-Degree Heart Block Type I

Wenckebach ; Intermittent block - Pacemaker: SA Node - rate: atrial rate is normal; Ventricular rate slightly slower than atrial rate. - regularity: atria regular; ventricles always irregular in a pattern of grouped beating. Conduction: each sinus impulse is held at the AV nose for progressively longer times until one is blocked entirely; then the cycle starts over.

CAN SINUS BRADYCARDIA CAUSE TROUBLE FOR THE PATEINT?

YES

CAN SINUS TACHYCARDIA CAUSE TROUBLE FOR THE PATEINT?

YES

Rules for Third-Degree Heart Block (CHB)

aka: Complete Heart Block Regularity: Regular Rate: Atrial Rate - usually normal (60-100 bpm) Ventricular Rate - 40-60 bpm if focus is junctional; 20-40 bpm if focus is ventricular. P Wave: Upright and uniform; more P Waves then QRS complexes. PRI: No relationship between P waves and QRS; P waves can occasionally be found superimposed on the QRS complex. QRS: : Less than 0.12 second if focus is junctional; 0.12 second or greater is focus is ventricular.

Rules for Second-Degree Heart Block Type I

aka: Wenckebach Regularity: Irregular; R-R interval changes as PRI gets longer; characteristic grouped beating. Rate: Usually slightly slower than normal P Wave: Upright and uniform; some P waves now followed by QRS complexes. PRI: Progressively prolonged PRI until one P wave is not conducted. QRS: less than .12 seconds

MULTIFOCAL

arising from many locations

A junctional impulse will depolarize the ventricles in a normal manner when

at about the same time that the atria are being depolarized with retrograde conduction.

Quadrigeminy

every 4th beat is a PVC

Bigeminy

every other beat is a PVC

Trigeminy

every third beat is a PVC

GROUPED BEATING

frequently occurring PVCs will fall into a pattern with the surrounding normal beats.

Second-Degree Type I (Wenckebach):

intermittent block (each beat is progressively delayed until one is blocked)

Second-Degree Type II:

intermittent block (selectively lets some beats through and blocks others)

Agonal

is the term used to describe a terminal, lethal arrhythmia, especially when it has stopped beating in a reliable pattern; also called a dying heart.

All junctional arrhythmias will have a PRI of

less than 0.12 seconds

First-Degree:

not actually a block

A junctional rhythm can have the inverted P wave

occurring before, during, or after the QRS complex.

An ectopic focus:

originates outside of the SA node.

A QRS measurement of less than 0.12 second indicates

supraventricular pacemaker.

Junctional arrhythmias will create an inverted P wave because

the atria are depolarized via retrograde conduction.

Runs of PVC's

three or more PVCs occurring in succession

COUPLETS

two PVCs occur before the normal pattern resumes

A compensatory pause

usually follows a PVC. This means that the distance between the R wave of the complex preceding the PVC and the R wave of the complex following the PVC is exactly twice the R-R interval of the underlying rhythm.

• Premature Ventricular Complex (PVC) • Ventricular Tachycardia • Ventricular Fibrillation • Idioventricular Rhythm • Asystole

ventricular arrhythmias

3rd degree heart block

• Atria and ventricles are completely dissociated • There is a total block at the AV node

2nd degree block type 1

• Intermittent block: some beats are conducted, others are blocke • Pathology can be within the AV node or below it in the Bundle of His • 2:1 AV Block • Pathology is often blended with other types of block

2nd degree block type 2

• Intermittent block: some beats are conducted, others are blocked • Pathology can be within the AV node or below it in the Bundle of His • 2:1 AV Block • Pathology is often blended with other types of block

Rhythms that originate in the sinus node include:

• Normal Sinus Rhythm • Sinus Bradycardia • Sinus Tachycardia • Sinus Arrhythmia

1st degree block

• Not a true block • Delay at the AV node • Each impulse is eventually conducted

arrhythmias that originates in the AV

• Premature Junctional Complex • Junctional Escape Rhythm • Accelerated Junctional Rhythm • Junctional Tachycardia

Rhythm Strip Analysis Format:

• Regularity (Rhythm) • Rate • P Waves • PR Intervals • QRS Complexes