2. Objectives
Review the cardiac physiology with respect to age, and age
related normals
Discuss wave morphology and axis as it relates to age and
ventricular dominance
Review intervals and other “differences” in the pediatric
ECG
Discuss an approach to interpretation of chamber
enlargement
Review some basic tachyarrythmias common in children
Normal variants and osce on ECG
3. Background
ECG changes during the first year of life reflect the switch
from fetal to infant circulation, changes in SVR, and the
increasing muscle mass of the LV
The size of the ventricles changes as the infant grows into
childhood and adulthood
The RV is larger and thicker at birth because of the
physiologic stresses on it during fetal development
By approximately 1 month of age, the LV will be slightly
larger
By 6 months of age, the LV is twice the size of the RV,
and by adolescence it is 2.5 times the size
4. Heart rate
Average heart rate peaks at second month of life, then
gradually decreases
Resting HRs start at 140 bpm at birth, fall to 120 bpm
at 1 year, 100 bpm at 5 years, and adult ranges by 10
years
5. •• INTRINSIC HEART RATESINTRINSIC HEART RATES
Newborn to 3 years:Newborn to 3 years:
• SA node 95 – 120
• AV node (junctional) 45 – 85
• Purkinje (ventricular) 35 – 55
3 years to teenager
• SA node 55 – 120
• AV node (junctional) 35 – 65
• Purkinje (ventricular) 25 45‐
6. Age Related Normal Findings
Tables exists that include age
based normal ranges for heart
rate, QRS axis, PR and QRS
intervals, and R and S wave
amplitudes
After infancy, changes become
more subtle and gradual as the
ECG becomes more like that of
an adult
7. The P Wave
Best seen in leads II and V1
P wave amplitude does not change significantly
during childhood
Amplitudes of 0.025 mV should be regarded as
approaching the upper limit of normal
8. The QRS Complex
QRS complex duration is shorter,
presumable because of decreased muscle
mass
QRS complexes > 0.08 sec in patients < 8
years is pathologic
In older children and adolescence a QRS
duration > 0.09 sec is also pathologic
9. The T Wave
The T waves are frequently upright throughout the
precordium in the first week of life
Thereafter, T waves in V1-V3 invert and remain
inverted from the newborn period until 8 years of
age
This is called the “juvenile T wave pattern”, and
can sometimes persist into adolescence
Upright T waves in the right precordial leads in
children can indicate right ventricular hypertrophy
11. QRS Axis and Ventricular Dominance
At birth, the axis is markedly rightward
(+60 - +160), the R/S ratio is high in V1
and V2 (large precordial R waves), and low
in V5 and V6
As the LV muscle mass grows and becomes
dominant the axis gradually shifts (+10 -
+100) by 1 year of age, and the R wave
amplitude decreases in V1 and V2 and
increases in V5 and V6
20. Atrial Enlargement
RAE is diagnosed in the
presence of a peaked tall P
wave in II
In the first 6 months, the P
wave must be >3 mm to
be pathologic; then >2
mm is abN
LAE can be diagnosed
with a biphasic P wave in
V1 with a terminal
inferior component
The finding of a notched P
wave in II can be a normal
variant in 25% of pediatric
ECGs
22. RVH
Large R wave in V1 and
large S wave in V6
Upright T wave in V1-V3
RAD
Persistent pattern of RV
dominance
Right Ventricular
Hypertrophy
Diagnosis depends on age
adjusted values for R
wave and S wave
amplitudes
A qR complex or rSR’
pattern in V1 can also be
seen
Upright T waves in the
right precordial leads,
RAD, and complete
reversal of adult
precordial pattern of R
and S waves all suggest
RVH
Lead V1with the R height
> 15 mm IN < 1YR & >10mm
IN > 1 YR
25. LVH
R wave > 98th
percentile in
V6 and S wave > 98th
percentile in V1
LV “strain” pattern in V5
and V6 or deep Q waves
in left precordial leads
“Adult” precordial R wave
progression in the neonate
26. CONDUCTIONCONDUCTION
ABNORMALITIESABNORMALITIES
Bundle branch blocks are diagnosed as they would
be in adults; RBBB occurs most commonly after
repair of congenital heard defects and LBBB is
very rare
First degree AV block and Mobitz type 1
(Wenckebach) can be a normal variant in 10% of
kids
Complete AV block is usually congenital or
secondary to surgery
27. Sinus Bradycardia
Deviation from NSR
- Rate < 60 bpm
Etiology: SA node is depolarizing slower than
normal, impulse is conducted normally (i.e.
normal PR and QRS interval).
28. Sinus Tachycardia
Deviation from NSR
- Rate > 100 bpm
Etiology: SA node is depolarizing faster
than normal, impulse is conducted
normally.
Remember: sinus tachycardia is a response
to physical or psychological stress, not a
primary arrhythmia.
33. 50 bpm• Rate?
• Regularity? regularly irregular
nl, but 4th no QRS
0.08 s
• P waves?
• PR interval? lengthens
• QRS duration?
Interpretation? 2nd Degree AV Block, Type I
34. 2nd Degree AV Block, Type I
Deviation from NSR
PR interval progressively lengthens, then
the impulse is completely blocked (P wave
not followed by QRS).
35. 40 bpm• Rate?
• Regularity? regular
nl, 2 of 3 no QRS
0.08 s
• P waves?
• PR interval? 0.14 s
• QRS duration?
Interpretation? 2nd Degree AV Block, Type II
36. 2nd Degree AV Block, Type II
Deviation from NSR
Occasional P waves are completely
blocked (P wave not followed by QRS).
Etiology: Conduction is all or nothing (no
prolongation of PR interval); typically block
occurs in the Bundle of His.
MOBITZ TYPE 2
37. Rhythm #13
40 bpm• Rate?
• Regularity? regular
no relation to QRS
wide (> 0.12 s)
• P waves?
• PR interval? none
• QRS duration?
Interpretation? 3rd Degree AV Block
47. Paroxysmal supraventricular tachycardia
(PSVT)
Regularity: Regular
Rate : >180/min
P wave morphology: Different from sinus P
wave or lost in preceeding T wave
PR interval: 0.12 – 0.20 secs ( normal)
QRS interval: normal (<0.08 s)
Pattern: Sudden onset and offset
48. Diagnosis
What is the rate?
Is the QRS wide or
narrow?
Causes
Ventricular tachycardia
56. Atrial Flutter
Deviation from NSR
No P waves. Instead flutter waves (note
“sawtooth” pattern) are formed at a rate of
250 - 350 bpm.
Only some impulses conduct through the
AV node (usually every other impulse).
58. 1. 2 year old with syncope and VT
LONG QT SYNDROMELONG QT SYNDROME
59. Intervals
PR and QRS durations are relatively short from birth to
age 1 and gradually lengthen during childhood; corrected
QT (QTc) should be calculated on all pediatric ECGs
During the first 6 mo of life, the QTc is slightly longer and
is considered normal below 0.49 sec
After that, any QTc above 0.44 sec is abnormal
Other features of long QT syndrome include notched T
waves, abnormal U waves, relative bradycardia and T
wave alternans
61. LONG QT – SYNDROME.
N-QTc- Infants 0.44 & NB-0.49sec
1.Beta-Blockers .Avoid drugs known to prolong
QT-interval , electrolyte imbalance.
2.SOS pacemaker . W/F Syndromes associated
with Long QT-interval.
3. Avoid competitive sports and swimming,
teach CPR to the caretakers. Inform about SIDS.
62. 14-year old girl
•Asymptomatic now
•Intermittent palpitations, no syncope
•SO2: 94%
•Split S2, multiple heart sounds, no
murmurs
CASE 2CASE 2
65. There is marked LVH (S wave in V2 > 35
mm) with dominant S waves in V1-4.
Right axis deviation suggests associated
right ventricular hypertrophy
(i.e. biventricular enlargement).
There is evidence of left atrial
enlargement (deep, wide terminal portion of
the P wave in V1).
There are peaked P waves in lead II
suggestive of right atrial hypertrophy (not
quite 2.5mm in height).
67. • Changes appear when K+ falls below about 2.7
mmol/l
• Increased amplitude and width of the P wave
• Prolongation of the PR interval
• T wave flattening and inversion
• ST depression
• Prominent U waves
(best seen in the precordial leads)
• Apparent long QT interval due
to fusion of the T and U waves
HYPOKALEMIA-HYPOKALEMIA-
ECGECG
5.
71. Station 1.a 1 day old neonate with respiratory distress ECG done
What are ECG features?
What is diagnosis?
What disorders are associated?
What precaution to be taken in emergency with such patients
7)
72. Inverted p/t wave, -ve qrs in lead 1.lead 2 n 3
reversed.lead 2 resemble 3 and 3 resemble 2
DEXTROCARDIA
number of bowel, esophageal, bronchial and
cardiovascular disorders (such as double outlet
right ventricle, endocardial cushion defect and
pulmonary stenosis) Kartagener syndrome
Place rt Up N lt Lo lead on Up lft N Lo rt
74. Station No;9
A 10 day old newborn was rushed to NICU by a local doctor as he found
different pattern of his cardiac activity. O/E child had fine rashes over the
face specially the periorbital area . ECG done in ER showed (1x5=5)
a) What is the ECG diagnosis? b )What is probable diagnosis?
c) What is the pathogenesis of this disease?
d) What is the Rx of this acute stage?
e) What is the earliest age at which this cardiac defect can detected antenatally?
75. A)COMPLETE HEART BLOCK
b) Neonatal Lupus
c) Transfer of anti Ro antibodies between 12-16
wks of gestation
d) Cardiac pacing
e) 16 wks of GA
76. 10
2 months old baby admitted with recurrent cough
cold, irritability, dyspnea and sweating. EKG done
What is the diagnosis? (1/2)
Name 4 EKG findings that helped u in diagnosis (1)
What is the diagnostic test?(1/2)
Name treatment options of it.(1)
77. Answer
ALCAPAALCAPA
Inverted T wave, V5-V6 deep Q wave,ST
elevation , inverted T wave
Cardiac catherization
Medical t/ t for CCF, ishamia and Surgical
excision and ligation
78. ALCAPA_ECG # Description : ECG. Left axis deviation with left
ventricular hypertrophy. Signs of anterolateral myocardial infarction:
deep Q waves with T waves inversions in leads I, avL and deep Q
waves with ST elevation in the left precordial leads.
79. A 12 yr old male child with c/o jt pain and fever admitted in ER.ECG
done showed.
What does this EKG strip shows (1)
Name 3 EKG findings that helped you in diagnosis (1)
What are the 2 clinical findings which will indicates severity?(1)
Name treatment options of it.(1)
What are other differential diagnosis?(1)
11
80. Answer
RHEUMATIC PERICARDITIS
Low voltage QRS, elevation of ST, Twave
inversion
Friction Rub and Pulsus Paradoxus
steroid
Viral Pericarditis, Benign Pericarditits, JRA
86. ECG showing R wave in lead V1 with RS in V2 (sudden transition),
Right axis deviation , no q waves in lateral leads suggesting decreased
pulmonary blood flow
TETROLOGY OF FALLOT (TOF)15
88. ASDASD
There is right axis deviation with tall R waves
V1-3 and corresponding deep S waves in V4-6. T waves are flat in
V1 and inappropriately upright in V2-3. There is the RsR' pattern in
V1 of partial rightbundle branch block.
17
91. Normal Variants
Sinus arrythmia
Can be quite marked
Slows on expiration and
speeds up on inspiration
Extrasystoles
Can be atrial or venticular
and are usually benign in
the context of a structurally
normal heart; typically
monomorphic and
associated with slower heart
rates
Abolish with excercise
93. In Summary
Consider the age of the child, and the
cardiac forces that may be dominant
Use a structured approach and assess
morphology, axis, and intervals in the
context of age related normals
Evaluate for the presence of structural
disease
Remember the “normal variants”