Lec 24: Diagnostics in Cardiology II: Pediatric ECG Flashcards
What are the anatomic and physiologic changes in the pediatric heart?
- ventricular hypertrophy- at birth, RV is larger than LV
(LV becomes larger by 1 month) - T wave - normally upright in the neonate (inverts in lead 1 by 7 days of age until 7 y.o.)
- QRS axis - at birth, range is +60 deg to +160. normal adult range is 0 to +90
- Resting Heart Rate - faster than adult HR:
birth - 140 beats/min
1 y.o. - 120 beats/min
5 y.o. - 100 beats/min
5-10 y.o. - adult values - intervals - PR interval, QRS duration, QT interval initially short
Where is Lead II placed?
right arm - left leg
Where is aVF placed?
left foot
Where is lead V5 placed?
5th ICS, left anterior axillary line
Which leads are used in pediatric patients?
15 lead ECG is used:
12 adult leads + V3R, V4R, and V7
Where do you expect tall QRS?
Pedia: V4R, V1, and V2
Adult: V5 and V6
(location of LV)
What is the value of a small square in the ECG?
0.04 s
How is atrial rate measured in the ECG?
PT interval
Why are atrial and ventricular rates counted separately?
to check for possible heart blocks
Which leads are used to identify axis deviation?
I and aVF
How do you measure heart rate at a glance?
count number of LARGE squares between the same points (usually R wave) on consecutive QRS complexes
300, 150, 100, 75, 60, 50
How can you tell a rhythm is ectopic based on the ECG?
left atrial rhythm - inverted P wave in I and aVL
low right atrial or coronary sinus rhythm - inverted P wave in II, III, and avF
What are common normal variations in rhythm?
- pronounced sinus arrhythmia
- short sinus pauses
- first degree AV block
- Mobitz type 1 2nd degree AV block
- junctional rhythm
- ventricular or supraventricular rhythm
What are the EKG findings for right atrial enlargement?
peaked P wave usually seen in lead II
What are the EKG findings for left atrial enlargement?
biphasic and notched P waves usually seen in leads I and II
