Pediatric Cardiology

Pediatric ECG (Electrocardiogram): Procedure, Uses and Results

Posted on by Prof. Dr. İbrahim Cansaran TANIDIR

Pediatric ECG (Electrocardiography) is a completely painless and reliable diagnostic test that transfers the natural electrical signals produced by the heart onto paper or a screen through tiny sensors attached to the chest, arms, and legs.

This practical method is performed without inserting any needles or making any incisions in the body. By recording the cardiovascular system’s functioning at a particular moment, it provides highly critical data regarding its structure and conduction system.

This electrocardiographic recording procedure, which takes only seconds and is performed on children’s delicate bodies, quickly eliminates concerns that are often a source of anxiety for parents. It is one of the most important steps in ensuring safety and establishing a diagnosis to maintain a healthy heart rhythm.

The precise planning of appropriate interventions in advanced cardiological treatments offered by modern medicine becomes possible through the careful evaluation of these unique electrical waves drawn by the device.

Why is ECG recording in children different from that in adults?

The fundamental factor distinguishing a child’s ECG recordings from the fixed ECG patterns of adulthood is that the child’s heart is continuously growing and adapting to changing physiological conditions. This process begins during the baby’s life in the mother’s womb, continues through the first moments of entering the outside world, and progresses very dynamically until the end of adolescence. Since the baby does not breathe in the womb, the lungs have not yet expanded, and vascular resistance in this region is extremely high. The right side of the heart, which must pump blood against this high resistance, has a thicker and stronger structure than the left side during the prenatal period. Therefore, when examining the Pediatric ECG results of a newborn baby, the electrical patterns indicating the dominance of the right side of the heart are particularly prominent.

When the baby is born, takes the first breath, and begins to cry, the lungs fill with air. With this expansion, the high resistance in the pulmonary vessels suddenly decreases, and the left side of the heart gradually begins to assume responsibility for pumping blood throughout the body. As months and years pass, the left heart muscle becomes progressively stronger, while the right heart muscle remains relatively thinner. This remarkable anatomical and physiological transformation causes the electrical waveforms, durations, and axes on the Pediatric ECG paper to change continuously. ECG findings considered normal in a one-week-old baby, a three-year-old child, and a fifteen-year-old adolescent are completely different from one another. Careful analysis of these age-specific transitional stages in children’s heart development increases the accuracy of ECG evaluation.

How does heart rate change with age in Pediatric ECG results?

Heart rate is determined by a child’s circulatory system’s immediate energy requirements, age, and degree of nervous system maturity, and this variation is one of the most notable aspects of Pediatric ECG recordings. The period when the heart beats fastest throughout human life is during the first weeks after birth. A baby’s small heart chambers must contract and relax very rapidly to meet the metabolic requirements of the rapidly growing body and deliver sufficient blood to the tissues.

During the neonatal period, a baby’s heart may beat approximately 120 to 160 times per minute. Although this speed may occasionally appear concerning to parents, it is a physiologically expected condition from a medical perspective. As the baby grows and enters infancy, the calming parasympathetic tone in the nervous system increases, and the heart rate decreases to between 80 and 140 beats per minute. By school age, this rate generally settles between 70 and 110 beats per minute, while during adolescence it slows to approximately 60 to 100 beats per minute, similar to adult values.

Another common physiological condition during childhood is the fluctuation of heart rhythm with breathing. Heart rate increases slightly during inhalation and slows during exhalation. This condition is called respiratory sinus arrhythmia and is generally considered a healthy finding indicating that the autonomic nervous system is functioning harmoniously and does not require concern.

Which symptoms indicate the need for a Pediatric ECG?

Problems that may involve the heart in children can present with very different clinical manifestations depending on the communication abilities and anatomical size of the age group. In young babies who cannot yet express themselves through words, a disturbance in the heart’s functioning may become apparent through indirect behaviors. When these findings are present, a Pediatric ECG examination may initially be used to determine whether the problem originates from the heart.

Suspicious symptoms that may be related to the heart in infants and newborns include:

  • Restlessness
  • Paleness
  • Sweating
  • Fatigue
  • Rapid breathing (tachypnea)
  • Failure to gain weight
  • Frequent waking
  • Bluish discoloration

Particularly, frequently stopping during feeding to catch their breath and unusual forehead sweating may indicate that a baby’s heart is working excessively hard. As children grow and begin to express what they experience in their bodies, their complaints become more direct.

Complaints that may require an ECG in school-aged children and adolescents include:

  • Palpitations
  • Dizziness
  • Fainting
  • Chest pain

Although chest pain in children is generally caused by growing pains or muscle spasms, the possibility that pain increasing during exertion may originate from the heart should not be overlooked. In particular, fainting episodes occurring during exercise, running, or sudden excitement should be evaluated without delay using a Pediatric ECG, as they may indicate an underlying structural problem or a dangerous rhythm disorder. Electrocardiographic evaluations are also highly beneficial in health screenings of young people who are about to begin licensed sporting activities, helping identify potential risks.

What information do the waves on a Pediatric ECG recording provide?

The ECG device illustrates the journey of electricity generated by the heart’s natural pacemaker as it spreads from the atria to the ventricles by drawing waves identified with specific letters on paper. The “P” wave represents the electrical activation of the atria, which are the upper chambers of the heart. The width and height of this wave may provide clues about whether the upper chambers of the heart are enlarged.

The time required for electricity to travel from the upper chambers to the lower chambers is called the “PR interval.” Since the heart is very small in babies, this distance is extremely short, measured in milliseconds. However, as the child grows, the volume of the heart muscle increases, and the distance electricity must travel becomes longer. If this PR interval is very short for the child’s age, the presence of congenital accessory pathways that allow electricity to take a shortcut through the heart may be suspected. A prolonged PR interval, on the other hand, may indicate slowing in the main electrical pathways.

The “QRS complex” represents ventricular contraction. Widening of this group of waves, which is expected to be thin and narrow in children, may suggest delays or blocks in the heart’s internal conduction branches. The resting phase during which the heart electrically recharges itself after contraction is monitored through the “T” wave. After the first week of life, this wave usually becomes negative and points downward in the right chest region (in lead V1). This condition, medically known as the Juvenile T-wave pattern, is an expected finding until adolescence. By examining the behavior of this wave on the ECG of a child undergoing healthy development, pressure differences in the right or left ventricle may be predicted.

How can rhythm disorders be diagnosed with a Pediatric ECG?

Disruptions in the generation or conduction of electrical impulses in children’s hearts may lead to rhythm disorders, also known as arrhythmias. One of the commonly encountered arrhythmias during childhood is Supraventricular Tachycardia (SVT), which causes the heart to beat much faster than normal. These episodes are often caused by an additional electrical connection pathway (accessory pathway) between the atria and ventricles that is present from birth but becomes active later.

Wolff-Parkinson-White (WPW) syndrome is one of the best-known examples of this condition. Under normal circumstances, the heart’s electrical impulses pass from the upper chambers to the lower chambers through a single filtering center. However, in WPW, an additional accessory pathway allows electricity to pass directly into the lower chambers without going through this main filter. In Pediatric ECG results, this shortcut is largely identified by the “delta wave” at the beginning of the QRS complex, which resembles a steep slope.

Occasionally, an electrical circuit may form between this shortcut and the normal pathway. When electricity begins circulating inside the heart like a spinning top, the heart rate may suddenly increase to 200-250 beats per minute. An ECG recorded during these tachycardia episodes, when the child describes sudden palpitations, shortness of breath, and weakness, provides invaluable guidance to physicians in understanding the mechanism of the arrhythmia and planning long-term treatment.

How are congenital heart defects reflected in Pediatric ECG results?

Although an ECG does not directly capture an image of the heart’s muscular structure, changes in the electrical map inside the heart may provide very valuable information about anatomical problems. Congenital holes in the heart or valve abnormalities alter the circulation and pressure of blood within the heart. These pressure changes cause certain heart chambers to work harder and, over time, become enlarged and increase their muscle mass. The thickened muscle mass then pulls the heart’s main electrical axis toward that side.

In Atrial Septal Defect (ASD), where the wall between the heart’s atria does not close completely, blood flows from the left side to the right side. This increases the workload of the right ventricle, causing it to enlarge. In Pediatric ECG recordings, this enlargement may be observed through a characteristic electrical pattern called right bundle branch block.

In defects in the wall between the ventricles (VSD), or when the large vascular connection that should close at birth remains open (PDA), large amounts of blood travel to the lungs and return from there to the left side of the heart. This additional blood volume enlarges the left ventricle. In this case, the voltages of the waves in the left heart region on the ECG may increase significantly compared with those of children of the same age. In complex structural conditions such as Atrioventricular Septal Defect (AVSD), the heart’s electrical axis may shift far beyond its normal position to a different angle, allowing the underlying structural problem to be suspected even through electrocardiographic evaluation alone.

How can genetically inherited heart problems and rhythm disorders be detected with the help of a Pediatric ECG?

Although rare in childhood, one group of conditions that requires serious attention is ion channel diseases (channelopathies). In these genetically inherited diseases, the child may have no holes in the heart, muscle enlargement, or vascular narrowing; the heart’s physical structure may appear completely normal. However, structural or functional abnormalities exist in the microscopic sodium or potassium channels located in heart cell membranes that are responsible for generating electricity.

Long QT Syndrome and Brugada Syndrome are among the leading genetic diseases that can be detected with the help of an ECG. After a normal heart contracts, it must electrically rest and recharge within very short periods, such as tenths of a second, to prepare for the next beat. In Long QT Syndrome, this resting period of the heart cells (the QT interval on the ECG recording) lasts longer than normal due to a genetic defect.

Although the child may appear completely healthy externally, prolongation may be identified when this QT interval is calculated on the ECG. This prolongation may predispose the heart to a dangerous rhythm disturbance when exposed to triggers such as a sudden loud sound (for example, a ringing bell), jumping into cold water, or excessive physical exertion. Therefore, carefully measuring the resting phase known as repolarization in routine ECG recordings or those performed due to complaints plays a major role in preventing potential sudden health problems.

Which advanced tests can be performed if abnormalities are found in Pediatric ECG results?

A standard ECG recorded in a hospital or clinic captures approximately 10-15 seconds of heart activity. Since some palpitation episodes or electrical problems may occur only under certain conditions, the ECG recorded at that moment may appear completely normal. If the child’s complaints continue or minor suspicious details are noticed in the initial ECG findings, various advanced evaluation methods may be used to examine the condition more thoroughly.

Advanced tests that may be planned after a Pediatric ECG include:

  • 24-hour Rhythm Holter monitoring
  • Echocardiography
  • Exercise stress test
  • Cardiac MRI
  • Catheterization/Angiography

Each of these methods evaluates the heart from a different perspective. For children whose palpitations are triggered at different times of the day or during sleep, daily variations can be observed using a Rhythm Holter device that continuously records heart rhythm for 24 to 48 hours. If symptoms occur only while running or exerting effort, the heart’s electrical responses to stress can be examined by performing an exercise stress test on specially adjusted treadmills.

If electrocardiography results raise suspicion of thickening in the heart muscle or a hole in the heart, Color Doppler Echocardiography, which displays the heart’s structure in real time using ultrasound waves, is performed without delay. When it is necessary to directly measure the extent of structural problems and pressures within the vessels, cardiac catheterization is performed in an angiography laboratory to determine the treatment plan. If conduction (electrical) problems are suspected, an Electrophysiological Study (EPS) may be performed to understand the cause of the condition.

How are electrophysiological studies and ablation treatments performed after a Pediatric ECG?

Treatment of rhythm disorders detected in children’s hearts is no longer limited to long-term medication use, as modern interventional methods can provide highly comfortable treatment options. In tachycardia episodes whose type has been largely identified through Pediatric ECG or Holter recordings, an Electrophysiological Study (EPS) may be performed in specialized catheterization laboratories at hospitals.

Since this procedure is performed under general anesthesia or light sedation, children do not experience pain or stress. Very thin, flexible tubes (catheters) with tiny electrical sensors at their tips are introduced through blood vessels in the child’s groin and guided into the heart. With computer-assisted three-dimensional mapping systems that minimize radiation (X-ray) exposure, a three-dimensional model of the inside of the heart is created on the screen. Small electrical impulses delivered into the heart trigger palpitations, and the abnormal focus responsible for the rhythm disorder is identified with millimeter-level precision.

Once the problematic area is located, a procedure called ablation is performed during the same session. Two different ablation methods are commonly used. In radiofrequency (RF) ablation, energy delivered through the catheter tip heats the tissue and disables the point generating abnormal electrical signals. In cryoablation (cold ablation), the catheter tip is cooled to a specific temperature. Particularly in sensitive areas very close to normal electrical pathways, the tissue is first temporarily frozen; if this does not adversely affect the normal heart rhythm, permanent freezing is then performed. These procedures, which have a high safety profile in children, aim to prevent the recurrence of the vast majority of tachycardia problems.

In which situations might pacemakers and defibrillators be necessary based on Pediatric ECG findings?

Electrocardiography results can reveal not only situations in which the heart beats excessively fast but also those in which the heart rate is far below the required level or electrical conduction is interrupted. Particularly in children whose heart rate is excessively low for their age group or whose electrical connection between the upper and lower chambers of the heart has lost its function (complete heart block), support for the heart’s mechanical pumping action may be necessary.

Conditions that may require a pacemaker include:

  • Advanced heart blocks
  • Sinus node problems
  • Severe bradycardia

In such cases of bradycardia, permanent pacemakers may be implanted to achieve a physiological heart rate, increase the child’s exercise capacity, and prevent fainting episodes. These devices are usually placed under the skin in the chest region, or in the abdominal region in small infants, to continuously regulate the heart rhythm.

On the other hand, children at risk of potentially fatal irregular ventricular fibrillation (VF) due to conditions such as inherited Long QT Syndrome or serious heart muscle diseases (cardiomyopathy) require a different device. These devices, called Implantable Cardioverter Defibrillators (ICDs), continuously monitor the heart’s rhythm and immediately deliver a small electrical shock to restore normal rhythm when a life-threatening rhythm disturbance begins. The use of these devices may be vitally important for the long-term safety of high-risk cases.

How can heart defects and vascular narrowings identified by Pediatric ECG be repaired without surgery?

In previous years, congenital heart defects (ASD, VSD, PDA), whose presence was supported by pressure findings or right/left axis deviations in Pediatric ECG recordings, were primarily treated with open-heart surgery involving opening the chest. Today, however, thanks to modern transcatheter (catheter-based) approaches performed by pediatric interventional cardiology specialists, many heart defects and vascular narrowings can be repaired without surgery.

Structurally suitable holes between the heart’s atria (ASD) or ventricles (VSD) can be closed using special umbrella-like devices (occluders) delivered to the heart through thin, flexible tubes inserted into blood vessels in the groin. When these devices reach the defect, they expand on both sides, closing the opening like a plug. Over time, they become covered by the heart’s own inner lining, forming a permanent wall. Similarly, in persistent vascular connections (PDA), leakage is prevented using wire coils or occlusion devices.

Additionally, congenitally narrowed heart valves or narrowed sections of major vessels such as the aorta can be widened without surgery through balloon angioplasty. When a specially designed deflated balloon is positioned in the narrowed area and inflated under high pressure, the fused valve leaflets open or the vessel expands. When necessary, a stent is placed inside the vessel to reduce the risk of narrowing again. The greatest advantage of all these procedures is that the child can generally be discharged from the hospital the following day without requiring intensive care or being left with a large surgical scar on the chest. The diagnostic process that begins with an ECG, a small reflection of the heart’s electrical world, combines with advanced treatment methods to provide extensive opportunities for children to return to their social lives, play, and education in a healthy manner.

Güncellenme Tarihi: 13.10.2026

Leave a Reply

Your email address will not be published. Required fields are marked *

Call Now Button