Pediatric ECG Learning App
This page is designed to assist students and doctors in learning and understanding pediatric ECGs. It provides a comprehensive guide to reading and interpreting electrocardiograms in children, highlighting the unique aspects and variations compared to adult ECGs. Whether you're a student aiming to master ECG interpretation or a healthcare professional seeking to refine your skills, this resource offers valuable insights into the nuances of pediatric cardiac monitoring.
Explore detailed sections on ECG basics, waveforms, intervals, and common pathologies to enhance your knowledge and diagnostic accuracy. The content is tailored to address the specific challenges of pediatric ECG interpretation, making it an essential tool for anyone involved in the care and assessment of young patients. Dive into the information provided to gain a clearer understanding of how to accurately read and analyze pediatric ECGs.
ECG Basics:
The pediatric electrocardiogram (ECG) is a valuable tool for assessing the electrical activity of a child's heart. Here are the basic components:
- Electrodes: Sensors placed on the skin to detect electrical activity.
- Leads: Views of the heart's electrical activity from different angles.
- Paper speed: Usually 25 mm/sec, which affects the interpretation of wave durations.
- Calibration: Standard calibration is 1 mV = 10 mm.
P Wave:
The P wave represents atrial depolarization. It is the first positive deflection in the ECG waveform.
- Normal duration: < 0.08 seconds in infants and children.
- Normal amplitude: < 2.5 mm in the limb leads.
- Abnormalities can indicate atrial enlargement or other atrial pathology.
QRS Complex:
The QRS complex represents ventricular depolarization. It consists of three waves: Q wave, R wave, and S wave.
- Normal duration: 0.04 - 0.08 seconds in infants and children.
- Pathological Q waves can indicate previous myocardial infarction.
- Wide QRS complex can indicate ventricular hypertrophy or bundle branch block.
T Wave:
The T wave represents ventricular repolarization. It follows the QRS complex.
- Normal T waves are asymmetrical.
- T wave inversion can be normal in children up to the age of 8 years, especially in the right precordial leads.
- Peaked T waves can indicate hyperkalemia.
U Wave:
The U wave represents the repolarization of the Purkinje fibers. It is sometimes seen following the T wave.
- Usually small and not always visible.
- Prominent U waves can indicate hypokalemia or bradycardia.
PR Interval:
The PR interval is the time from the beginning of the P wave to the start of the QRS complex, indicating the time taken for electrical activity to travel from the atria to the ventricles.
- Normal duration: 0.10 - 0.14 seconds in infants and children.
- Prolonged PR interval can indicate first-degree heart block.
- Shortened PR interval can indicate pre-excitation syndromes like Wolff-Parkinson-White syndrome.
QRS Interval:
The QRS interval represents the duration of ventricular depolarization.
- Normal duration: 0.04 - 0.08 seconds in infants and children.
- Wide QRS complex can indicate ventricular hypertrophy or bundle branch block.
- Narrow QRS complex is typically seen in supraventricular tachycardia.
QT Interval:
The QT interval is the time from the start of the QRS complex to the end of the T wave, representing the total time for ventricular depolarization and repolarization.
- Normal duration varies with heart rate; QTc (corrected QT) is used for standardization. In children, the upper limit of normal QTc is around 0.44 seconds.
- Prolonged QT interval can indicate risk for ventricular arrhythmias like torsades de pointes.
- Shortened QT interval can indicate hypercalcemia.
Myocardial Infarction:
Myocardial infarction (MI) in children presents with several key ECG changes:
- Presence of Q waves.
- ST-segment elevation in the leads corresponding to the affected area.
- T wave inversion.
Atrial Fibrillation:
Atrial fibrillation in children is characterized by an irregularly irregular rhythm with no distinct P waves.
- Irregular R-R intervals.
- Absence of discrete P waves, replaced by fibrillatory waves.
Ventricular Tachycardia:
Ventricular tachycardia (VT) is a fast heart rhythm originating from the ventricles.
- Wide QRS complexes (>0.12 seconds).
- Regular rhythm with a fast rate (>100 bpm in children).
Heart Block:
Heart blocks in children are categorized into first, second, and third-degree blocks, each with distinct ECG features:
- First-degree: Prolonged PR interval (>0.20 seconds).
- Second-degree: Dropped beats (Mobitz type I and II).
- Third-degree: Complete dissociation between atrial and ventricular activity.
