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Wandering Atrial Pacemaker Multifocal Atrial Tachycardia Atrial Tachycardia Premature Atrial Contractions Paroxysmal Supraventricular Tachycardia Atrial Flutter Atrial Fibrillation

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Page 1: Wandering Atrial Pacemaker  Multifocal Atrial Tachycardia  Atrial Tachycardia  Premature Atrial Contractions  Paroxysmal Supraventricular Tachycardia

Wandering Atrial Pacemaker Multifocal Atrial Tachycardia Atrial Tachycardia Premature Atrial Contractions Paroxysmal Supraventricular

Tachycardia Atrial Flutter Atrial Fibrillation

Page 2: Wandering Atrial Pacemaker  Multifocal Atrial Tachycardia  Atrial Tachycardia  Premature Atrial Contractions  Paroxysmal Supraventricular Tachycardia

NormalQRS

NormalPRI

Changes from beat to beat P Waves

VariesPacemaker Site

Slightly IrregularRhythm

Usually normalRate

Wandering Pacemaker

Rules of Interpretation

Page 3: Wandering Atrial Pacemaker  Multifocal Atrial Tachycardia  Atrial Tachycardia  Premature Atrial Contractions  Paroxysmal Supraventricular Tachycardia

Wandering PacemakerEtiology

Transfer of pacemaker sites from the sinus node to other latent pacemaker sites in the atria and AV junction

A variant of sinus dysrhythmia, a normal phenomenon in the very young or the aged, Ischemic heart disease, atrial dilation

Clinical significance Usually has no detrimental effects Precursor of other atrial dysrhythmias such as

atrial fibrillation Treatment

If the patient is symptomatic, consider adenosine or verapamil

Page 4: Wandering Atrial Pacemaker  Multifocal Atrial Tachycardia  Atrial Tachycardia  Premature Atrial Contractions  Paroxysmal Supraventricular Tachycardia

VariableQRS

Varies depending on source of impulse

PRI

Organized, nonsinus P waves; at least 3 formsP Waves

Ectopic sites in atriaPacemaker Site

IrregularRhythm

More than 100Rate

Multifocal Atrial Tachycardia

Rules of Interpretation

Page 5: Wandering Atrial Pacemaker  Multifocal Atrial Tachycardia  Atrial Tachycardia  Premature Atrial Contractions  Paroxysmal Supraventricular Tachycardia

Multifocal Atrial TachycardiaEtiology

Often seen in acutely ill patients May result from pulmonary disease, metabolic

disorders, ischemic heart disease, or recent surgery

Clinical Significance Presence of multifocal atrial tachycardia often

indicates a serious underlying illnessTreatment

Treat the underlying illness

Page 6: Wandering Atrial Pacemaker  Multifocal Atrial Tachycardia  Atrial Tachycardia  Premature Atrial Contractions  Paroxysmal Supraventricular Tachycardia

Usually normalQRS

Varies dependent on foci of impulse

PRI

Occurs earlier than expected

P Waves

Ectopic sites in atriaPacemaker Site

Usually regular except for the PAC

Rhythm

Depends on underlying rhythm

Rate

Premature Atrial Contractions

Rules of Interpretation

Page 7: Wandering Atrial Pacemaker  Multifocal Atrial Tachycardia  Atrial Tachycardia  Premature Atrial Contractions  Paroxysmal Supraventricular Tachycardia

Premature Atrial ContractionsEtiology

Single electrical impulse originating outside the SA node

May result from use of caffeine, tobacco, or alcohol, sympathomimetic drugs, ischemic heart disease, hypoxia, or digitalis toxicity, or may be idiopathic

Clinical Significance None. Presence of PACs may be a precursor to

other atrial dysrhythmias.Treatment

None if asymptomatic. Treat symptomatic patients by administering high-flow, high-concentration oxygen and establishing IV access.

Page 8: Wandering Atrial Pacemaker  Multifocal Atrial Tachycardia  Atrial Tachycardia  Premature Atrial Contractions  Paroxysmal Supraventricular Tachycardia

Usually normalQRS

Usually normalPRI

Often buried in preceding T wave

P Waves

Atrial (outside SA Node)

Pacemaker Site

RegularRhythm

150–250Rate

Paroxysmal Supraventricular Tachycardia

Rules of Interpretation

Page 9: Wandering Atrial Pacemaker  Multifocal Atrial Tachycardia  Atrial Tachycardia  Premature Atrial Contractions  Paroxysmal Supraventricular Tachycardia

Paroxysmal Supraventricular TachycardiaEtiology

Rapid atrial depolarization overrides the SA node May be precipitated by stress, overexertion,

smoking, caffeineClinical Significance

May be tolerated well by healthy patients for short periods

Marked reduction in cardiac output can precipitate angina, hypotension, or congestive heart failure

Page 10: Wandering Atrial Pacemaker  Multifocal Atrial Tachycardia  Atrial Tachycardia  Premature Atrial Contractions  Paroxysmal Supraventricular Tachycardia

Paroxysmal Supraventricular TachycardiaTreatment

Vagal Maneuvers Pharmacological Therapy

Adenosine Electrical Therapy

Consider if patient symptomatic with HR >150. Synchronized cardioversion starting at 50-100 J (or

biphasic equivalent

Page 11: Wandering Atrial Pacemaker  Multifocal Atrial Tachycardia  Atrial Tachycardia  Premature Atrial Contractions  Paroxysmal Supraventricular Tachycardia

NormalQRS

Usually normalPRI

Difficult to seeP Waves

In the atriaPacemaker Site

RegularRhythm

150-250 bpmRate

Supraventricular Tachycardia

Rules of Interpretation

Page 12: Wandering Atrial Pacemaker  Multifocal Atrial Tachycardia  Atrial Tachycardia  Premature Atrial Contractions  Paroxysmal Supraventricular Tachycardia

Supraventricular TachycardiaEtiology

Refers to tachycardias that originate above the ventricles

Use of caffeine, nicotine, or alcohol, cocaine sympathomimetic drugs, ischemic heart disease

Clinical Significance Rapid rates can cause a marked reduction in

cardiac output because of inadequate ventricular filling time

Treatment Manage with tachycardia algorithm

Page 13: Wandering Atrial Pacemaker  Multifocal Atrial Tachycardia  Atrial Tachycardia  Premature Atrial Contractions  Paroxysmal Supraventricular Tachycardia

Click here to view the Tachycardia Management diagram.Reproduced with permission from “2005 American Heart Association Guidelines for Cardiopulmonary

Resuscitation and Emergency Care,” Circulation 2005, Volume 112, IV-70. © 2005 American Heart Association.

Page 14: Wandering Atrial Pacemaker  Multifocal Atrial Tachycardia  Atrial Tachycardia  Premature Atrial Contractions  Paroxysmal Supraventricular Tachycardia

Usually normalQRS

Usually normalPRI

F waves are present

P Waves

Atrial (outside SA node)

Pacemaker Site

Usually regularRhythm

Atrial rate 250–350Ventricular rate variesRate

Atrial Flutter

Rules of Interpretation

Page 15: Wandering Atrial Pacemaker  Multifocal Atrial Tachycardia  Atrial Tachycardia  Premature Atrial Contractions  Paroxysmal Supraventricular Tachycardia

Atrial FlutterEtiology

Results when the AV node cannot conduct all the impulses Impulses may be conducted in fixed or variable

ratios Usually associated with organic disease such as

congestive heart failure (rarely seen with MI)Clinical Significance

Generally well tolerated Rapid ventricular rates may compromise cardiac

output and result in symptoms May occur in conjunction with atrial fibrillation

Page 16: Wandering Atrial Pacemaker  Multifocal Atrial Tachycardia  Atrial Tachycardia  Premature Atrial Contractions  Paroxysmal Supraventricular Tachycardia

Atrial FlutterTreatment

Electrical Therapy Consider if ventricular rate >150 and symptomatic Synchronized cardioversion starting at 100 J

Pharmacological Therapy Diltiazem or beta blockers Do not use a calcium channel and beta blockers

concomitantly

Page 17: Wandering Atrial Pacemaker  Multifocal Atrial Tachycardia  Atrial Tachycardia  Premature Atrial Contractions  Paroxysmal Supraventricular Tachycardia

NormalQRS

NonePRI

None discernibleP Waves

Atrial (outside SA Node)Pacemaker Site

Irregularly irregularRhythm

Atrial rate 350–750Ventricular rate variesRate

Atrial Fibrillation

Rules of Interpretation

Page 18: Wandering Atrial Pacemaker  Multifocal Atrial Tachycardia  Atrial Tachycardia  Premature Atrial Contractions  Paroxysmal Supraventricular Tachycardia

Atrial FibrillationEtiology

Results from multiple ectopic foci; AV conduction is random and highly variable

Often associated with underlying heart diseaseClinical Significance

Atria fail to contract effectively, reducing cardiac output

Well tolerated with normal ventricular rates High or low ventricular rates can result in cardiac

compromise

Page 19: Wandering Atrial Pacemaker  Multifocal Atrial Tachycardia  Atrial Tachycardia  Premature Atrial Contractions  Paroxysmal Supraventricular Tachycardia

Atrial FibrillationTreatment

Electrical Therapy Consider if ventricular rate >150 and symptomatic Synchronized cardioversion starting at 100 J

Pharmacological Therapy Diltiazem or beta blockers

Page 20: Wandering Atrial Pacemaker  Multifocal Atrial Tachycardia  Atrial Tachycardia  Premature Atrial Contractions  Paroxysmal Supraventricular Tachycardia

AV junction serves two important physiological purposes:Slows the impulse between the atria and

the ventricles Backup pacemaker if the SA node or cells

higher in the conductive system fail to fire

Page 21: Wandering Atrial Pacemaker  Multifocal Atrial Tachycardia  Atrial Tachycardia  Premature Atrial Contractions  Paroxysmal Supraventricular Tachycardia

AV BlocksLocations

At the AV node At the Bundle of His Below the Bundle of

HisClassifications

First-Degree AV block Type I Second-Degree

AV block Type II Second-Degree

AV block Third-Degree AV block

Page 22: Wandering Atrial Pacemaker  Multifocal Atrial Tachycardia  Atrial Tachycardia  Premature Atrial Contractions  Paroxysmal Supraventricular Tachycardia

Usually <0.12 seconds

QRS

>0.20 SecondsPRI

NormalP Waves

SA node or atrialPacemaker Site

Usually regularRhythm

Depends on underlying rhythm

Rate

First-Degree AV Block

Rules of Interpretation

Page 23: Wandering Atrial Pacemaker  Multifocal Atrial Tachycardia  Atrial Tachycardia  Premature Atrial Contractions  Paroxysmal Supraventricular Tachycardia

First-Degree AV BlockEtiology

Delay in the conjunction of an impulse through the AV node

May occur in healthy hearts, but often indicative of ischemia at the AV junction

Clinical Significance Usually not significant, but new onset may

precede a more advanced blockTreatment

Generally, none required other than observation Avoid drugs that may further slow AV conduction

Page 24: Wandering Atrial Pacemaker  Multifocal Atrial Tachycardia  Atrial Tachycardia  Premature Atrial Contractions  Paroxysmal Supraventricular Tachycardia

Usually <0.12 secondsQRS

Increases until QRS is dropped, then repeatsPRI

Normal, some P waves not followed by QRSP Waves

SA node or atrialPacemaker Site

Atrial, regular; ventricular, irregular

Rhythm

Atrial, normal; ventricular, normal to

slowRate

Type I Second-Degree AV Block

Rules of Interpretation

Page 25: Wandering Atrial Pacemaker  Multifocal Atrial Tachycardia  Atrial Tachycardia  Premature Atrial Contractions  Paroxysmal Supraventricular Tachycardia

Type I Second-Degree AV BlockEtiology

Also called Mobitz I, or Wenckebach Delay increases until an impulse is blocked Indicative of ischemia at the AV junction

Clinical Significance Frequently dropped beats can result in cardiac

compromiseTreatment

Generally, none required other than observation Avoid drugs that may further slow AV conduction Treat symptomatic bradycardia

Page 26: Wandering Atrial Pacemaker  Multifocal Atrial Tachycardia  Atrial Tachycardia  Premature Atrial Contractions  Paroxysmal Supraventricular Tachycardia

Normal or >0.12 secondsQRS

Constant for conducted beats, may be >0.21 secondsPRI

Normal, some P waves not followed by QRSP Waves

SA node or atrialPacemaker Site

May be regular or irregular

Rhythm

Atrial, normal; ventricular, slow

Rate

Type II Second-Degree AV Block

Rules of Interpretation

Page 27: Wandering Atrial Pacemaker  Multifocal Atrial Tachycardia  Atrial Tachycardia  Premature Atrial Contractions  Paroxysmal Supraventricular Tachycardia

Type II Second-Degree AV BlockEtiology

Also called Mobitz II or infranodal Intermittent block of impulses Usually associated with MI or septal necrosis

Clinical Significance May compromise cardiac output and is indicative

of MI Often develops into full AV blocks

Treatment Avoid drugs that may further slow AV conduction Treat symptomatic bradycardia

Consider transcutaneous pacing Atropine

Page 28: Wandering Atrial Pacemaker  Multifocal Atrial Tachycardia  Atrial Tachycardia  Premature Atrial Contractions  Paroxysmal Supraventricular Tachycardia

Normal or >0.12 secondsQRS

Constant for conducted beats, may be >0.21 secondsPRI

2 P waves for each QRSP Waves

SA node or atrialPacemaker Site

RegularRhythm

Atrial, normal; ventricular, slow

Rate

2:1 AV Block

Rules of Interpretation

Page 29: Wandering Atrial Pacemaker  Multifocal Atrial Tachycardia  Atrial Tachycardia  Premature Atrial Contractions  Paroxysmal Supraventricular Tachycardia

2:1 AV BlockEtiology

Second degree AV block where there are two P waves for each QRS

Associated with acute myocardial infarction and septal necrosis

Clinical significance Can compromise cardiac output Can develop into full AV block

Treatment Prepare for transcutaneous pacing Atropine

Page 30: Wandering Atrial Pacemaker  Multifocal Atrial Tachycardia  Atrial Tachycardia  Premature Atrial Contractions  Paroxysmal Supraventricular Tachycardia

0.12 seconds or greaterQRS

No relationship to QRSPRI

Normal, with no correlation to QRS

P Waves

SA node and AV junction or ventricle

Pacemaker Site

Both atrial and ventricular are regularRhythm

Atrial, normal; ventricular, 40–60

Rate

Third-Degree AV Block

Rules of Interpretation

Page 31: Wandering Atrial Pacemaker  Multifocal Atrial Tachycardia  Atrial Tachycardia  Premature Atrial Contractions  Paroxysmal Supraventricular Tachycardia

Third-Degree AV Block (Complete Heart Block)Etiology

Absence of conduction between the atria and the ventricles

Results from AMI, digitalis toxicity, or degeneration of the conductive system

Clinical Significance Severely compromised cardiac output

Treatment Transcutaneous pacing for acutely symptomatic

patients Treat symptomatic bradycardia Avoid drugs that may further slow AV conduction

Page 32: Wandering Atrial Pacemaker  Multifocal Atrial Tachycardia  Atrial Tachycardia  Premature Atrial Contractions  Paroxysmal Supraventricular Tachycardia

DysrhythmiasPremature junctional contractions Junctional escape complexes and rhythm Junctional bradycardiaAccelerated junctional rhythm

Characteristics of all junctional rhythms Inverted P Waves in Lead IIPRI of <0.12 SecondsNormal QRS Complex Duration

Page 33: Wandering Atrial Pacemaker  Multifocal Atrial Tachycardia  Atrial Tachycardia  Premature Atrial Contractions  Paroxysmal Supraventricular Tachycardia

Usually normalQRS

Normal if P occurs before QRS

PRI

Inverted, may occur after QRS

P Waves

Ectopic focus in the AV junction

Pacemaker Site

Depends on underlying rhythm

Rhythm

Depends on underlying rhythm

Rate

Rules of InterpretationPremature Junctional Contractions

Page 34: Wandering Atrial Pacemaker  Multifocal Atrial Tachycardia  Atrial Tachycardia  Premature Atrial Contractions  Paroxysmal Supraventricular Tachycardia

Premature Junctional ContractionsEtiology

Single electrical impulse originating in the AV node May occur with use of caffeine, tobacco, alcohol,

sympathomimetic drugs, ischemic heart disease, hypoxia, or digitalis toxicity, or may be idiopathic

Clinical Significance Limited, frequent PJCs may be precursor to other

junctional dysrhythmiasTreatment

None usually required

Page 35: Wandering Atrial Pacemaker  Multifocal Atrial Tachycardia  Atrial Tachycardia  Premature Atrial Contractions  Paroxysmal Supraventricular Tachycardia

Usually normalQRS

Normal if P occurs before QRS

PRI

Inverted, may occur after QRS

P Waves

AV junctionPacemaker Site

Irregular in single occurrence, regular

in escape rhythmRhythm

40–60Rate

Junctional Escape Complexes and Rhythms

Rules of Interpretation

Page 36: Wandering Atrial Pacemaker  Multifocal Atrial Tachycardia  Atrial Tachycardia  Premature Atrial Contractions  Paroxysmal Supraventricular Tachycardia

Junctional Escape Complexes and RhythmsEtiology

Results when the AV node becomes the pacemaker Results from increased vagal tone, pathologically

slow SA discharges, or heart blockClinical Significance

Slow rate may decrease cardiac output, precipitating angina and other problems

Treatment None if the patient remains asymptomatic Treat symptomatic episodes with atropine or pacing

Page 37: Wandering Atrial Pacemaker  Multifocal Atrial Tachycardia  Atrial Tachycardia  Premature Atrial Contractions  Paroxysmal Supraventricular Tachycardia

Usually normal, may be greater than 0.12

QRS

Normal if P occurs before QRS

PRI

Inverted, may occur after QRS

P Waves

AV junctionPacemaker Site

Irregular in single occurrence, regular in

escape rhythmRhythm

Less than 40Rate

Junctional Bradycardia

Rules of Interpretation

Page 38: Wandering Atrial Pacemaker  Multifocal Atrial Tachycardia  Atrial Tachycardia  Premature Atrial Contractions  Paroxysmal Supraventricular Tachycardia

Junctional BradycardiaEtiology

Junctional dysrhythmia with a heart rate less than the intrinsic rate of the AV node

Increased vagal tone, pathological slow SA node discharge, heart block, intrinsic disease

Clinical Significance Decreased cardiac output

Treatment Prepare for transcutaneous pacing Consider Atropine

Page 39: Wandering Atrial Pacemaker  Multifocal Atrial Tachycardia  Atrial Tachycardia  Premature Atrial Contractions  Paroxysmal Supraventricular Tachycardia

NormalQRS

Normal if P occurs before QRS

PRI

Inverted, may occur after QRS

P Waves

AV junctionPacemaker Site

RegularRhythm

60–100Rate

Accelerated Junctional Rhythm

Rules of Interpretation

Page 40: Wandering Atrial Pacemaker  Multifocal Atrial Tachycardia  Atrial Tachycardia  Premature Atrial Contractions  Paroxysmal Supraventricular Tachycardia

Accelerated Junctional RhythmEtiology

Results from increased automaticity in the AV junction

Often occurs due to ischemia of the AV junctionClinical Significance

Usually well tolerated, but monitor for other dysrhythmias

Treatment None generally required in the prehospital

setting

Page 41: Wandering Atrial Pacemaker  Multifocal Atrial Tachycardia  Atrial Tachycardia  Premature Atrial Contractions  Paroxysmal Supraventricular Tachycardia

NormalQRS

Normal if P occurs before QRS

PRI

Inverted, may occur after QRS

P Waves

AV junctionPacemaker Site

RegularRhythm

60-100Rate

Accelerated Junctional Rhythm

Rules of Interpretation

Page 42: Wandering Atrial Pacemaker  Multifocal Atrial Tachycardia  Atrial Tachycardia  Premature Atrial Contractions  Paroxysmal Supraventricular Tachycardia

Accelerated Junctional RhythmEtiology

Results from increased automaticity in the AV junction

Ischemia of the AV junction Clinical Significance

Patient should be monitored for other dysrhythmias Treatment

Prehospital treatment generally is unnecessary

Page 43: Wandering Atrial Pacemaker  Multifocal Atrial Tachycardia  Atrial Tachycardia  Premature Atrial Contractions  Paroxysmal Supraventricular Tachycardia

Ventricular escape complexes and rhythms

Accelerated idioventricular rhythm

Premature ventricular contraction

Ventricular tachycardia

Torsades de pointes

Ventricular fibrillation

Asystole Artificial

pacemaker rhythm

Page 44: Wandering Atrial Pacemaker  Multifocal Atrial Tachycardia  Atrial Tachycardia  Premature Atrial Contractions  Paroxysmal Supraventricular Tachycardia

>0.12 seconds, bizarreQRS

NonePRI

NoneP Waves

VentriclePacemaker Site

Escape complex, irregular;escape rhythm, RegularRhythm

15–40Rate

Ventricular Escape Complexesand Rhythms

Rules of Interpretation

Page 45: Wandering Atrial Pacemaker  Multifocal Atrial Tachycardia  Atrial Tachycardia  Premature Atrial Contractions  Paroxysmal Supraventricular Tachycardia

Ventricular Escape Complexes and RhythmsEtiology

Safety mechanism to prevent cardiac standstill Results from failure of other foci or high-degree

AV blockClinical Significance

Decreased cardiac output, possibly to life-threatening levels

Treatment For perfusing rhythms, administer atropine

and/or TCP For nonperfusing rhythms, follow pulseless

electrical activity (PEA) protocols

Page 46: Wandering Atrial Pacemaker  Multifocal Atrial Tachycardia  Atrial Tachycardia  Premature Atrial Contractions  Paroxysmal Supraventricular Tachycardia

>0.12 seconds, bizarre

QRS

NonePRI

NoneP Waves

VentriclePacemaker Site

Escape complex, irregular;escape rhythm, RegularRhythm

60-100Rate

Accelerated Idioventricular Rhythm

Rules of Interpretation

Page 47: Wandering Atrial Pacemaker  Multifocal Atrial Tachycardia  Atrial Tachycardia  Premature Atrial Contractions  Paroxysmal Supraventricular Tachycardia

Accelerated Idioventricular RhythmEtiology

A subtype of ventricular escape rhythm that frequently occurs with MI

Ventricular escape rhythm with a rate of 60–110Clinical Significance

May cause decreased cardiac output if the rate slows

Treatment Does not usually require treatment unless the

patient becomes hemodynamically unstable Primary goal is to treat the underlying MI

Page 48: Wandering Atrial Pacemaker  Multifocal Atrial Tachycardia  Atrial Tachycardia  Premature Atrial Contractions  Paroxysmal Supraventricular Tachycardia

>0.12 seconds, bizarreQRS

NonePRI

NoneP Waves

VentriclePacemaker Site

Interrupts regular underlying rhythm

Rhythm

Underlying rhythmRate

Premature Ventricular Contractions

Rules of Interpretation

Page 49: Wandering Atrial Pacemaker  Multifocal Atrial Tachycardia  Atrial Tachycardia  Premature Atrial Contractions  Paroxysmal Supraventricular Tachycardia

Premature Ventricular Contractions Etiology

Single ectopic impulse resulting from an irritable focus in either ventricle

Myocardial ischemia, increased sympathetic tone, hypoxia, idiopathic causes, acid-base disturbances, electrolyte imbalances, or as a normal variation of the ECG

May occur in patterns Bigeminy, trigeminy, or quadrigeminy Couplets and triplets

Page 50: Wandering Atrial Pacemaker  Multifocal Atrial Tachycardia  Atrial Tachycardia  Premature Atrial Contractions  Paroxysmal Supraventricular Tachycardia

Premature Ventricular ContractionsClinical Significance

Malignant PVCs More than 6/minute, R on T phenomenon, couplets

or runs of ventricular tachycardia, multifocal PVCs, or PVCs associated with chest pain

Ventricles do not adequately fill, causing decreased cardiac output

Page 51: Wandering Atrial Pacemaker  Multifocal Atrial Tachycardia  Atrial Tachycardia  Premature Atrial Contractions  Paroxysmal Supraventricular Tachycardia

Premature Ventricular ContractionsTreatment

Nonmalignant PVCs do not usually require treatment in patients without a cardiac history

Cardiac patient with nonmalignant PVCs Administer oxygen and establish IV access

Malignant PVCs: Lidocaine 1.0 –1.5 mg/kg IV bolus Repeat doses of 0.5-0.75 mg/kg to max dose of 3.0

mg/kg If PVCs are suppressed, administer lidocaine drip 2–

4 mg/min Reduce the dose in patients with decreased output

or decreased hepatic function and patients >70 years old

Page 52: Wandering Atrial Pacemaker  Multifocal Atrial Tachycardia  Atrial Tachycardia  Premature Atrial Contractions  Paroxysmal Supraventricular Tachycardia

>0.12 seconds, bizarre

QRS

NonePRI

If present, not associated with

QRSP Waves

VentriclePacemaker Site

Usually regularRhythm

100–250Rate

Ventricular Tachycardia

Rules of Interpretation

Page 53: Wandering Atrial Pacemaker  Multifocal Atrial Tachycardia  Atrial Tachycardia  Premature Atrial Contractions  Paroxysmal Supraventricular Tachycardia

Ventricular TachycardiaEtiology

3 or more ventricular complexes in succession at a rate of >100

Causes include myocardial ischemia, increased sympathetic tone, hypoxia, idiopathic causes, acid-base disturbances, or electrolyte imbalances

VT may appear monomorphic or polymorphic Torsade’s De Pointes

Clinical Significance Decreased cardiac output, possibly to life-

threatening levels May deteriorate into ventricular fibrillation

Page 54: Wandering Atrial Pacemaker  Multifocal Atrial Tachycardia  Atrial Tachycardia  Premature Atrial Contractions  Paroxysmal Supraventricular Tachycardia

Click here to view an animation on dysrhythmia.

Page 55: Wandering Atrial Pacemaker  Multifocal Atrial Tachycardia  Atrial Tachycardia  Premature Atrial Contractions  Paroxysmal Supraventricular Tachycardia

Click here to view the Tachycardia Management diagram.Reproduced with permission from “2005 American Heart Association Guidelines for Cardiopulmonary

Resuscitation and Emergency Care,” Circulation 2005, Volume 112, IV-70. © 2005 American Heart Association.

Page 56: Wandering Atrial Pacemaker  Multifocal Atrial Tachycardia  Atrial Tachycardia  Premature Atrial Contractions  Paroxysmal Supraventricular Tachycardia

Torsades de pointes Polymorphic VTUse of certain

antidysrhythmic drugs

Exacerbated by coadministration of antihistamines, azole antifungal agents and macrolide

Page 57: Wandering Atrial Pacemaker  Multifocal Atrial Tachycardia  Atrial Tachycardia  Premature Atrial Contractions  Paroxysmal Supraventricular Tachycardia

Torsades de pointesTypically occurs in nonsustained bursts

Prolonged QT interval during “breaks” QRS rates from 166–300 RR interval highly variable

Treatment Do not treat as standard VT Administer magnesium sulfate 1–2 g diluted in

100 ml D5W over 1–2 minutes Overdrive pacing

Page 58: Wandering Atrial Pacemaker  Multifocal Atrial Tachycardia  Atrial Tachycardia  Premature Atrial Contractions  Paroxysmal Supraventricular Tachycardia

NoneQRS

NonePRI

Usually absentP Waves

Numerous ventricular foci

Pacemaker Site

No organized rhythm

Rhythm

No organized rhythm

Rate

Ventricular Fibrillation

Rules of Interpretation

Page 59: Wandering Atrial Pacemaker  Multifocal Atrial Tachycardia  Atrial Tachycardia  Premature Atrial Contractions  Paroxysmal Supraventricular Tachycardia

Ventricular FibrillationEtiology

Wide variety of causes, often resulting from advanced coronary artery disease

Clinical Significance Lethal dysrhythmia with no cardiac output and

no organized electrical pattern

Page 60: Wandering Atrial Pacemaker  Multifocal Atrial Tachycardia  Atrial Tachycardia  Premature Atrial Contractions  Paroxysmal Supraventricular Tachycardia

Ventricular FibrillationTreatment

Initiate CPR Defibrillate with 360 J (or biphasic equivalent) Control the airway and establish IV access Administer epinephrine 1:10,000 every 3–5

minutes Consider 40 IU Vasopressin IV (one time only)

Consider second-line drugs Amiodarone Lidocaine

Provide continuous compressions

Page 61: Wandering Atrial Pacemaker  Multifocal Atrial Tachycardia  Atrial Tachycardia  Premature Atrial Contractions  Paroxysmal Supraventricular Tachycardia

AbsentQRS

AbsentPRI

AbsentP Waves

No Electrical Activity

Pacemaker Site

No Electrical Activity

Rhythm

No Electrical Activity

Rate

Asystole

Rules of Interpretation

Page 62: Wandering Atrial Pacemaker  Multifocal Atrial Tachycardia  Atrial Tachycardia  Premature Atrial Contractions  Paroxysmal Supraventricular Tachycardia

AsystoleEtiology

Primary event in cardiac arrest, resulting from massive myocardial infarction, ischemia, and necrosis

Final outcome of ventricular fibrillationClinical Significance

Asystole results in cardiac arrest Poor prognosis for resuscitation

Page 63: Wandering Atrial Pacemaker  Multifocal Atrial Tachycardia  Atrial Tachycardia  Premature Atrial Contractions  Paroxysmal Supraventricular Tachycardia

AsystoleTreatment

Administer CPR and manage the airway Treat for ventricular fibrillation if there is any

doubt about the underlying rhythm Administer medications:

Epinephrine and Atropine

Page 64: Wandering Atrial Pacemaker  Multifocal Atrial Tachycardia  Atrial Tachycardia  Premature Atrial Contractions  Paroxysmal Supraventricular Tachycardia

Click here to view the Pulseless Arrest diagram.Reproduced with permission from “2005 American Heart Association Guidelines for Cardiopulmonary

Resuscitation and Emergency Care,” Circulation 2005, Volume 112, IV-59. © 2005 American Heart Association.

Page 65: Wandering Atrial Pacemaker  Multifocal Atrial Tachycardia  Atrial Tachycardia  Premature Atrial Contractions  Paroxysmal Supraventricular Tachycardia

>0.12 seconds, bizarre

QRS

If present, variesPRI

None produced by ventricular pacemakers;

pacemaker spikeP Waves

Depends upon electrode placement

Pacemaker Site

May be regular or irregular

Rhythm

Varies with

pacemakerRate

Artificial Pacemaker

Rules of Interpretation

Page 66: Wandering Atrial Pacemaker  Multifocal Atrial Tachycardia  Atrial Tachycardia  Premature Atrial Contractions  Paroxysmal Supraventricular Tachycardia

Artificial Pacemaker RhythmEtiology

Single vs. dual chamber pacemakers Fixed-rate vs. demand pacemakers

Clinical Significance Used in patients with a chronic high-grade heart

block, sick sinus syndrome, or severe symptomatic bradycardia

Page 67: Wandering Atrial Pacemaker  Multifocal Atrial Tachycardia  Atrial Tachycardia  Premature Atrial Contractions  Paroxysmal Supraventricular Tachycardia

Artificial Pacemaker RhythmProblems with Pacemakers

Battery failure “Runaway” pacers Displaced leads

Management Considerations Identify patients with pacemakers Treat the patient

Use of a Magnet

Page 68: Wandering Atrial Pacemaker  Multifocal Atrial Tachycardia  Atrial Tachycardia  Premature Atrial Contractions  Paroxysmal Supraventricular Tachycardia

CharacteristicsElectrical impulses are present, but with

no accompanying mechanical contractions of the heart

Treat the patient, not the monitor Causes

Hypovolemia, cardiac tamponade, tension pneumothorax, hypoxemia, acidosis, massive pulmonary embolism, ventricular wall rupture

Page 69: Wandering Atrial Pacemaker  Multifocal Atrial Tachycardia  Atrial Tachycardia  Premature Atrial Contractions  Paroxysmal Supraventricular Tachycardia

TreatmentPrompt recognition and early treatmentEpinephrine 1 mg every 3–5 minutesTreat underlying cause of PEA

Page 70: Wandering Atrial Pacemaker  Multifocal Atrial Tachycardia  Atrial Tachycardia  Premature Atrial Contractions  Paroxysmal Supraventricular Tachycardia

Categories of Conductive DisordersAtrioventricular BlocksDisturbances of Ventricular ConductionPre-excitation Syndromes

Page 71: Wandering Atrial Pacemaker  Multifocal Atrial Tachycardia  Atrial Tachycardia  Premature Atrial Contractions  Paroxysmal Supraventricular Tachycardia

Disturbances of Ventricular ConductionAberrant Conduction

A single supraventricular beat conducted through the ventricles in a delayed manner

Bundle Branch Block All supraventricular beats are conducted through

the ventricles in a delayed manner Causes

Ischemia or necrosis of a bundle branch PAC or PJC that reaches one of the bundle

branches in a refractory periodDifferentiation of SVT and Wide-Complex

Tachycardias

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Pre-excitation SyndromesExcitation by an

impulse that bypasses the AV node Creates Delta wave slur

Wolff-Parkinson-White (WPW) syndrome Conduction from the

atria to the ventricles is abnormal

Associated with tachydysrhythmias

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Wolfe-Parkinson-White Syndrome

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HypokalemiaNormal potassium

levels are 3.5–-5.0 mEg/L

Flattened T waves Prominent U waves

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HyperkalemiaTall Ts

Suspect in patients with a history of renal failure

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HypocalcemiaCan be caused by

the use of diuretics and certain endocrine conditions

Prolongs ST segment

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HypercalcemiaCan be caused by

adrenal insufficiency, hyperparathyroidism, kidney failure, or malignancies

Shortens ST segment

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Digitalis useSagging or

scooping of the ST segment

Prolonged PR interval

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HypothermiaOsborn wave

(“J” wave)T wave

inversion, sinus bradycardia, atrial fibrillation or flutter, AV blocks, PVCs, VF, asystole

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Cardiovascular Anatomy Cardiovascular Physiology Electrocardiographic Monitoring Dysrhythmias