peadiatric ECG

PEDIATRIC ECGsPEDIATRIC ECGs

OBJECTIVESOBJECTIVES

1. Review Pediatric ECG Indications 2. Discuss some similarities and

differences between Pediatric and Adult ECGs

3. Discuss pediatric arrhythmias

Successful use of Pediatric Successful use of Pediatric ElectrocardiographyElectrocardiographyBe aware of age related differences in ECG

indications

Know N ranges for ECG variables

Recognize typical differences in infants/children

Indications for a Pediatric ECGIndications for a Pediatric ECG

Syncope/seizureExertional symptomsDrug ingestionsTachyarrhythmiaBradyarrhythmiaCyanotic episodesHeart FailureHypothermia

Electrolyte disturbanceKawasaki diseaseRheumatic feverMyocarditisMyocardial contusionPericarditisPost cardiac surgeryCongenital heart defects

““PAEDS ECG” + 2 FsPAEDS ECG” + 2 Fs

P- pericarditis (or myocarditis), post cardiac surgery

A-arrhythmias (tachy or bradyarrhythmia)

E-exertional symptomsD-drugs, disease (Kawasaki)S-syncope/seizure

E-electrolyte disturbanceC-cyanosis, contusion

(myocardial), cold (hypothermia)

G- conGenital heart defects

2 Fs:◦ Fever (rheumatic)◦ Failure (heart)

Chest Pain in KidsChest Pain in Kids

Rarely cardiac in origin

ECG NOT usually helpful in diagnosis

Consider ECG for parent reassurance

ECG RecordingECG RecordingDistract childLimb electrodes proximal, less movement artifactStandard adult positions, but add V3R or V4R to

detect right ventricular or atrial hypertrophyStandard paper speed (25 mm/s) and deflection (10

mm/mV)

AGE RELATED CHANGES IN AGE RELATED CHANGES IN NORMALNORMAL ECGs ECGs

The famous 1 complex, 2 The famous 1 complex, 2 segments, 2 intervals and 5 segments, 2 intervals and 5 waves.waves.

Heart development during infancy and childhood causes differences in HR, interval durations, and ventricular dominance

Abnormal adult ECG features may be Normal age-related changes in pediatrics

Pediatric ECG findings that may be Pediatric ECG findings that may be NormalNormal

HR > 100 bpmRight precordial T wave inversionDominant RPLs R wavesShort PR and QT intervalsShort P wave and short QRS durationInferior and lateral Q waves

Approach in reading Paediatric Approach in reading Paediatric ECGECG

Heart RateHeart Rate

CO = SV X HR

Higher rate for infant’s high metabolic needs, small ventricle size cannot compensate by increasing SV (newborn commonly 120-160 bpm)

As heart grows, SV increases. Higher rate no longer needed to produce adequate CO

Rate gradually declines with age

RESTING HRRESTING HRBirth 140 bpm

1 yr: 120 bpm

5 yr: 100 bpm

10 yr: adult values

P waveP wave

P axis in range 0 to +90°P waves upright in I, II & aVFP wave duration 0.06s +/- 0.02s in childrenMax P duration 0.1s in children & 0.08s in infants.E.g if P axis is in range of +90 to + 180º what would u

suspect in a normal healthy child?

PR IntervalPR Interval

P wave + physiologic delay in AV node (PQ segment)Varies with age & HR. Age increases, HR decreases & PR interval increases

in durationWith the exception the PR interval is longer in

duration at Birth than at infants period

PR IntervalPR Interval

Decreases from birth-1 yr, then gradually increases t/o childhood

AGE PR (ms)

Birth 80-160

6 m 70-150

1 yr 70-150

5 yr 80-160

10 yr 90-170

Ventricle DominanceVentricle DominanceFetal heart pumps blood to high resistance

pulmonary circuit, so RV pressure highAfter birth:

◦Pulmonary vascular resistance falls◦RV muscularity recedes◦RV contribution to ECG diminishes

Systemic vascular resistance changes: increased LV size until > than RV (1 month)

6 months: RV/LV ratio similar to adultsShift from newborn RV dominance to LV

dominance by 1 yr RV dominance: R wave is larger than S wave in V1

Heart ChangesHeart Changes

Neonates: RV larger than LV, so Normal to have:◦Right axis deviation◦Large precordial R

waves◦Upright T waves

30 weeks gestation 1.2 : 1

33 weeks gestation 1.0 : 1

36 weeks gestation 0.8 : 1

At birth 0.8 : 1

1 month 1.5 : 1

6months 2.0 : 1

Alduts 2.5 : 1

LV/RV Weight Ratio

D3oL babyRADDominant R in

V4R/V1Upright T in V1Upright T

persistence in RPLs > 1st wk: sign of RVH

12 year old ECGNormal adult

axisR wave no longer

dominant in R precordial leads

QRS axisQRS axisMean vector of Vent Depolarization

processBirth:

◦mean QRS axis +125° with RAD◦up to 180° can be normal in

newborn ◦R waves prominent in R

precordium◦S waves prominent in L

precordiumAxis moves to Left as child ages

Newborn +125°

1 month +90°

3 years +60°

adult +50°

QRSQRSVentricular

Depolarization time

QRS duration are short in the young infant & increases with age.

AGE QRS duration (ms)

Birth < 75

6 m < 75

1 yr < 75

5 yr < 80

10 yr < 85

Normal values in paediatric Normal values in paediatric electrocardiogramselectrocardiograms

R wave (S Wave) Amplitude (mm)

Age PR

Interval (ms)

QRS duration

(ms)

Lead V1 Lead V6

Birth 80 160 < 75 5 26(1 23) 0 12 (0 10)

6 months 70 150 < 75 3 20 (1 17) 6 22 (0 10)

1 year 70 150 < 75 2 20 (1 20) 6 23 (0 7)

5 years 80 160 < 80 1 16 (2 22) 8 25 (0 5)

10 years 90 170 < 85 1 12 (3 25) 9 26 (0 4)

Q wavesQ waves

Depolarization of Ventricular SeptumCommonly in I,II,III & aVFAlmost always in V5 & V6 but absent in V4R & V1Duration is 0.02s & not > 0.03sIn aVF & V5, max amplitude <6mmIn V6, should be <5mm

R/S ProgressionR/S ProgressionIn patient > 3 years of ageProgressive increase in R wave amplitude toward V5Progressive decrease in S wave amplitude toward V61st month of life, complete reversal of R/S progressionBtw 1mont & 3 years, partial reversal present with

dominant R in V1 as well as in V5 & V6

T wavesT waves

Ventricular repolarizationT axis is more anterior with upright T wave in V1T wave in V1 inverts (Posterior) by 7 days, stays

inverted until 5 to 7 years then progressively more anterior in later years

Upright T waves in right precordial leads (V1-V3) between 7d and 7yrs are ABNORMAL, usually RVH

QT intervalQT interval

Varies with HR but not age, except in infancyMust interpreted by Bazett’s formula QTcImportant in recognition of congenital prolonged QT

syndrome, and medication effects (ie hyperK+, hypoCa++, dig, quinidine, procainaminde, Li+, tricyclics, phenothiazides)

QTc should not exceed 0.44, except in infant where QTc of up to 0.49s may be normal for the 1st 6months of life.

(if can’t calculate, shouldn’t be > half R-R distance)

U waveU wave

Occur at the end of T waveShould not be included in QTcRepresents the repolarization of Purkinje fibersPresent in hypokalemia

Long QT syndrome in 3 yr oldLong QT syndrome in 3 yr old

ABNORMALABNORMAL PAEDIATRIC PAEDIATRIC ECGsECGs

Ventricular HypertrophyVentricular Hypertrophy“Voltage Criteria”: Depend on age adjusted values for R

and S wave amplitudes

R wave (S wave) amplitude (mm)

R wave (S wave) amplitude (mm)

AGE V1 V6

Birth 5-26 (1-23) 0-12 (0-10)

6 m 3-20 (1-17) 6-22 (0-10)

1 yr 2-20 (1-20) 6-23 (0-7)

5 yr 1-16 (2-22) 8-25 (0-5)

10 yr 1-12 (3-25) 9-26 (0-4)

RVHRVH

Useful ECG Features◦qR or rSR’ in V1◦Upright T in RPLs: 7d-7yrs

◦Marked right axis deviation (esp if with right atrial enlargement)

◦Complete reversal of adult precordial pattern of R and S waves

Pediatric RVHPediatric RVH

13 yr oldTransposition of great

arteries, previous Mustard’s

RV systemic ventricle: RVH

RADDominant R in R

precordial leads

Case: 6 m old with Cyanotic Episodes: ToF and RVHCase: 6 m old with Cyanotic Episodes: ToF and RVH

Tall R in V1, reciprocal S in V6

qR in V3R and V4R

RAD 120*Upright T V1-

V3 (should be inverted)

LVHLVHUseful ECG Features

◦Deep Qs in L precordial leads◦Lateral ST depression and T wave inversion

Some Congenital Heart Defects and ECG Some Congenital Heart Defects and ECG ManifestationsManifestations Anomalous L coronary

artery ◦ Anterolat MI

Anomalous pulm venous return◦ Total: RAD, RVH, RAH◦ Partial RVH or RBBB

Aortic Stenosis◦ LVH

Coarctation◦ < 6m: RBBB or RVH◦ > 6m: LVH, N, RBBB

Patent ductus arteriosus◦ Small shunt: N◦ Mod: LVH, +/- LAH◦ Large: CVH, LAH

Some Congenital Heart Defects and ECG Some Congenital Heart Defects and ECG ManifestationsManifestations

Persistent truncus arteriosus◦ LVH or CVH

Pulm atresia (and hypoplastic RV)◦ LVH

Tetralogy of Fallot◦ RAD, RVH, +/- RAH

Transposition◦ Intact septum: RVH, RAH◦VSD and/or PS: CVH, RAH,

or CAHCorrected transposition

◦AV blocks, WPW, LAH or CAH, absent Q in V5/V6, and qR in V1

ABNORMALITIESABNORMALITIES OF RATE AND OF RATE AND RHYTHMRHYTHM

Abnormal HRAbnormal HR

Consider systemic illness in any child with an abnormal HR

Sinus tachycardia in babies and infants can be up to 240 bpm

Bradycardia: consider hypoxia, sepsis, acidosis, intracranial lesions

Pediatric ArrhythmiasPediatric Arrhythmias

Any adult arrhythmia can occur in peds

Major difference in pediatric ECGs is type of abN rhythms usually seen

Most common pediatric dysrhythmias: SVT, bradycardia, and sinus arrhythmia

AF, atrial flutter, VT, or VF rareBUT: kids with congenital heart disease may

have any arrhythmia

What should be done about this ECG?What should be done about this ECG?

Nothing!Nothing!

Sinus arrhythmia common in children’s ECGsOften quite marked

Sinus ArrhythmiaSinus Arrhythmia

Inspiration: increased blood flow to heart decreases vagal tone: increased HR

Expiration: increased vagal tone: lower HRMarked in asthma, upper airway obstruction, increased ICP,

and premature infants (immature autonomic innervation)Must differentiate from AF Rarely in infants but N in many kids/athletes, normally

insignificant

Sinus BradycardiaSinus Bradycardia

Sinus rate below N for age: 80 in newborn is sinus brady; 50 in athletic teenager is N

Common in severe distress: hypoxia*/drugs

Can be asymptomatic/insignificant (ie sleep/well-conditioned), treat if signs of poor systemic perfusion

SVTSVTMost common paeds arrhythmiaCan occur in healthy infants and children

Different from sinus tach by unusually fast rate and patient presentation: ◦ST usually physiologic: fear, fever, hypovolemia◦SVT: vague hx, child irritable, lethargic, feeding poorly,

may present with signs of CHF

Regular rhythm > 220 (infants up to 280-320)

AV BlocksAV Blocks

Uncommon: atrial enlargement, surgical damage to AV nodal tissue, or congenital

Same classification as adults

1st degree AV block: must account for PR change with age. Can be N, or occur in rheumatic carditis, diphtheria, digoxin OD, and congenital heart defects

Other ArrhythmiasOther Arrhythmias

AF/flutter: rare in children Flutter: rheumatic heart dz, congenital defects,

cardiac surgery, in utero, or N neonatesVT: RARE, extremely abN: monomorphic associated

with heart surgery; polymorphic (torsades) with long QT syndrome

Aids to diagnose tachycardias (ie AV dissociation and capture/fusion beats) LESS common in kids

Other ArrhythmiasOther Arrhythmias

Atrial and Ventricular extrasystoles very common, usu benign if structurally N heart

VF: RARE, only ~ 10% of terminal rhythm; congenital heart dz, prolonged resuscitation efforts, prolonged QT or long QT syndrome

Asystole: common, least successfully resolved lethal peds arrhythmia; hypoxia and acidosis damage myocardium beyond repair

What What I HopeI Hope We Covered… We Covered…

1. Indications for Pediatric ECGs2. Some differences between Pediatric and Adult

ECGs3. Common pediatric arrhythmias

What You Should What You Should TRYTRY to to Remember…Remember…

Kids ‘n’ AdultsKids ‘n’ Adults

SIMILARITIESConduction pathways same,

so waveforms (P, QRS, T) same, and waveform timing measured the same (i.e., PR, QRS, QT interval)

Identical approach to ECG analysis

DIFFERENCESKids: fast HR that slows

with age, shorter N intervals that prolong with age, and diminution of RV dominance

Sinus bradycardia, sinus arrhythmia and SVT most common arrhythmias in kids

Findings that may be NFindings that may be N

HR > 100 bpmRight precordial T wave inversionDominant R precordial R wavesShort PR and QT intervalsShort P wave and short QRS durationInferior and lateral Q waves

REFERENCESREFERENCES

ABC of clinical electrocardiograpy. Paediatric electrocardiography. Goodacre S, McLeod K. BMJ Volume 324. June 8, 2002. Pgs 1382-1385

ECG INTERPRETATION: WHAT IS DIFFERENT IN CHILDREN? Mowery, Bernice, Suddaby, Elizabeth C., Pediatric Nursing, 0097-9805, May 1, 2001, Vol. 27, Issue 3.

How to interpret Paediatric ECG by Gunneroth