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Paediatric ECGCONTENTS

1.ECG2.Use of Paediatric ECGs3.Indications4.ECG recording in children5.Electrophysiology and anatomy6.Reference System7.Mechanic of tracing8.Basic measurement9.Normal ECGs10.Normal values and interpretation11.Common deviations from normal ECGs in children

Standard ECG12 leads ECG 2. Use of Paediatric ECGs1.To be aware of age related differences in ECG indications2.To know normal ranges for ECG variables 3. Indications for a Paediatric ECGSyncope/seizure Exertional symptoms Drug ingestions Tachyarrhythmia Bradyarrhythmia Cyanotic episodes Syncope/seizure Exertional symptoms Drug ingestions Tachyarrhythmia Bradyarrhythmia Cyanotic episodes Heart Failure Hypothermia Heart Failure Hypothermia Mnemonic form - PAEDS ECG + 2 Fs P pericarditis (or myocarditis), post cardiac surgeryA arrhythmias (tachy or bradyarrhythmia) E exertional symptoms D drugs, disease (Kawasaki) S syncope/seizure E electrolyte disturbance C cyanosis, contusion (myocardial), cold (hypothermia)G congenital heart defects 2 Fs: Fever (rheumatic) Failure (heart) 4. ECG recording in childrenDistract child Limb electrodes proximal, less movement artifactStandard adult positions, but add V3R or V4R to detect right ventricular or atrial hypertrophy

5. Electrophysiology and anatomy

12-lead ECG provides spatial information about the heart's electrical activity in 3 approximately orthogonal directions.Right to LeftSuperior to InferiorAnterior to Posterior

7. Mechanic of tracingSmall box = 1 x 1 mmLarge box = 5 x 5 mmECG 1

8. Basic measurementPaper speed (horizontal boxes)Standard = 25 mm/sec

9.Normal ECGs

P wavethe sequentialactivation (depolarization) of the right and left atriaQRS complexright and left ventricular depolarization (normally the ventricles are activated simultaneously)ST-T waveventricular repolarizationPR intervaltime interval from onset of atrial depolarization (P wave) to onset of ventricular depolarization (QRS complex)QRS durationduration of ventricular muscle depolarizationQT intervalduration of ventricular depolarization and repolarizationRR interval: duration of ventricular cardiac cycle (an indicator of ventricular rate)PP intervalduration of atrial cycle (an indicator of atrial rate)10. Normal values and interpretation

RateRhythmAxisIntervalsAtrial enlargementVentricular hypertrophyST/T wave evaluationDetermination of amplitudeAmplitude of ECG deflections are important for interpretation.Calibration gives the standardization of an ECG.

A - means 1 mV=10mmB - means limb leads are in full standardization but precordial leads are half standardized.C - means both precordial leads and limb are in half standardization.D - means limb leads are in half standardization but precordial leads are in 1/4 standardisation.E and F - show using two times the full standardization.

ECG 2

RateMeasured in beats per minuteMeasuring RR interval directly 1. 60 / RR interval (in seconds)2. 300 / number of big boxes between consecutive QRS complexes3. 1500 / number of little boxes between consecutive QRS complexes

ECG 3

RR intervalHow many seconds?9x0.04 = 0.36 sec 60 / 0.36 = 167 bpm How many big boxes between R and R?1.8 big boxes300 / 1.8 = 167 bpmHow many small boxes between R and R?9 small boxes1500/9 = 167 bpm

Count the heart rate.ECG 4

In cases with irregular rhythm

To count the number of beats in 6 second (30 big boxes)To multiply by 10ECG 5

Rhythm

Sinus rhythmTachyarrhythmiaBradyarrhythmiaAtrioventricular block

Axis

QRS deflectionAxis

Lead 1aVF

PositivePositiveNormal

PositiveNegativeLAD

NegativePositiveRAD

NegativeNegativeExtreme RAD or LAD

ECG 6

ECG 7

ECG 8