Cardiac Contractility Disorders in Children: Symptoms, Diagnosis and Treatment

Cardiac contraction disorders in children are serious cardiological conditions that occur when the pumping function of the heart decreases as a result of the myocardium being unable to contract sufficiently and in a coordinated manner. This condition may be associated with congenital cardiomyopathies (such as HCMP, DCMP, RCMP, ARVD), previous infections (such as Kawasaki, MIS-C, COVID), metabolic diseases, or genetic syndromes, and early diagnosis is critically important for prognosis.

Diagnostic methods for cardiac contraction disorders in children begin with a detailed physical examination and clinical evaluation and are supported by electrocardiography and echocardiography. Cardiac magnetic resonance imaging and biochemical markers make important contributions to determining the degree of myocardial function and the underlying cause.

Pediatric cardiomyopathy treatment options are planned according to the underlying etiology and the level of heart failure. While ACE inhibitors, beta blockers, aldosterone antagonists, and diuretics are used in medical treatment, some newer medications (such as ARB, ARNI, SGLT2 inh, ivabradine) may be considered in slightly older cases, and mechanical circulatory support or heart transplantation may come to the agenda in more advanced cases, requiring a multidisciplinary approach.

Long-term follow-up in cardiac contraction disorders in children includes regular monitoring of growth and development parameters and cardiac functions. While quality of life increases significantly in cases where early intervention is performed, regular follow-up and adherence to treatment are essential to reduce the risk of complications.

With Which Symptoms Do Cardiac Contraction Disorders in Children Manifest?

The symptoms of cardiac contraction disorders in children vary greatly according to the child’s age, physical development, and the rate of disease progression. While heart problems in adults usually appear with very typical complaints such as chest pain or numbness in the left arm, the condition in children may progress much more complexly and insidiously. Symptoms often appear extremely ordinary and may mimic other diseases. For example, it is not always easy to understand that a child who breathes rapidly as if having only a simple respiratory tract infection is actually experiencing a cardiac contraction disorder. In this process, the observations of families are the greatest help in making the correct diagnosis.

In infancy, heart problems usually reveal themselves through changes in feeding habits. For babies, breastfeeding or bottle-feeding is an activity that requires an incredible amount of effort, almost like heavy exercise. While a healthy baby tolerates this effort easily, a baby with a cardiac contraction disorder becomes exhausted quickly during this effort.

The most common symptoms encountered in infants are:

• Rapid breathing
• Excessive sweating
• Refusal to feed
• Fatigue while sucking
• Failure to gain weight
• Constant restlessness
• Paleness of the skin
• Weak pulse

When these symptoms appear, it should be remembered that the underlying cause is the heart’s inability to pump sufficient blood to the body. When blood flow decreases, the body reduces blood flow to the hands and feet in order to protect the vital organs, the brain and kidneys. This causes paleness and coldness of the skin and weakly felt pulses. In addition, strain on the heart leads to fluid accumulation in the lungs, causing the baby to breathe very rapidly and shallowly.

In preschool and school-age children, symptoms begin to take a slightly different form. Children in this period are more active, and limitations during physical activities can be observed more clearly.

The main symptoms seen in young children are as follows:

• Easy fatigue
• Exercise limitation
• Loss of appetite
• Unexplained abdominal pain
• Frequent recurrent vomiting
• Palpitations
• Swelling of the eyelids
• Edema in the legs

Children usually become tired much faster than their peers while playing and often feel the need to rest. When the heart cannot perform its duty properly, blood begins to pool in the liver and the liver enlarges. This enlargement causes severe abdominal pain and loss of appetite in the child. As adolescence approaches, more prominent and warning symptoms such as chest pain during exertion, shortness of breath, a feeling of palpitations, and even fainting (syncope) begin to come to the forefront, just as in adults. Especially experiencing shortness of breath while lying down at night and feeling the need to sleep on a high pillow are important signs indicating the seriousness of the condition.

How Does Myocarditis, Which Is Among the Causes of Cardiac Contraction Disorders in Children, Develop?

Myocarditis is inflammation of the heart muscle and is one of the most insidious and dangerous causes of cardiac contraction disorders in children. It usually appears after a seemingly simple flu, cold, or intestinal infection. However, the process is not as simple as a virus reaching the heart and causing damage. The disease involves a highly dramatic process in which the body accidentally attacks the heart while trying to protect itself. This process generally occurs in three distinct stages.

The first stage is the viral infection phase. The virus entering the body from outside reaches the heart muscle cells through the circulatory system and begins to multiply by entering these cells. As the virus multiplies, it destroys the cells and causes direct damage to the heart. This stage usually occurs within the first few days of the infection, and classic flu symptoms such as fever, weakness, and muscle pain are seen in the child.

The second stage is the immune system response phase, where things actually become complicated. The body’s defense mechanism launches a very strong attack to destroy the virus. White blood cells rush into the heart tissue. However, the protein structure of the virus is incredibly similar to the heart’s own healthy cell structure. The immune system experiences a condition called “cross-reaction” and confuses friend with foe. While trying to destroy the virus, it actually begins to violently attack the heart’s completely healthy muscle cells. This is the most critical stage determining how severe the disease will be.

The third stage is the restructuring, or remodeling, phase. This stage may last months to years. The inflammation may subside within months, but the damage it leaves in the heart tissue may be permanent. Damaged heart muscle cells lose their elasticity and are replaced by scar tissue (fibrosis). The heart muscle relaxes, the inner cavities of the heart enlarge, and contraction strength decreases significantly. This condition may turn into a chronic cardiac contraction disorder, that is, a cardiomyopathy picture that may last a lifetime.

Which Methods Are Used to Diagnose Cardiac Contraction Disorders in Children?

Time is very valuable in a child suspected of having a cardiac contraction disorder. It is not possible to make a definitive diagnosis only with physical examination or auscultation findings. Therefore, advanced technologies are needed to show the internal structure, electrical system, and contraction capacity of the heart at the millimetric level. With the development of technology, extremely detailed information can be obtained without tiring or frightening children.

The main methods used in the diagnostic process are:

• Echocardiography
• Electrocardiography
• Chest radiography
• Blood tests (such as BNP, Troponin, various viral tests)
• Magnetic resonance imaging (2nd best indicator)
• Endomyocardial biopsy (best indicator)
• Genetic tests

Echocardiography, that is, ultrasound of the heart, is the most basic and harmless tool of this process. Using sound waves, all chambers of the heart, the structure of the valves, and the speed of blood flow are displayed in color on the screen. The percentage of blood that the heart can pump to the body with each beat (ejection fraction) is clearly measured with this method.

Electrocardiography (ECG) creates the electrical map of the heart. Electrical signals generated when the heart contracts are recorded on paper through small patches attached to the skin. Whether there is thickening of the heart muscle, whether the rhythm functions regularly, or whether there is possible inflammation in the heart can be understood from subtle fluctuations on the ECG. However, a normal-looking ECG does not mean that the heart is completely healthy.

Magnetic Resonance (MR) Imaging has today become the gold standard especially in heart muscle inflammations (myocarditis) and in detecting inflammation within the tissue. Without giving radiation to the child, a three-dimensional and incredibly detailed map of the heart is created using a giant magnet and radio waves. Edema (fluid accumulation) or scars in the heart tissue can be seen this clearly only with MRI.

Endomyocardial biopsy is the procedure of taking a millimetric tissue sample from inside the heart and examining it under a microscope. It is the only method that definitively proves whether there is a virus in the heart muscle or whether the immune system is attacking the cells. However, since it is an invasive procedure, it is preferred not in every patient but only in special cases where diagnosis cannot be made or the condition worsens very rapidly.

What Are the Types of Cardiomyopathy Seen Among Cardiac Contraction Disorders in Children?

Cardiomyopathies are a group of diseases that directly disrupt the muscle structure of the heart and change the shape and contraction strength of the chambers. Although these diseases usually result from an error in the child’s genetic code, previous infections may also trigger this condition. They are divided into various subgroups according to the pattern of change in the heart muscle.

The most common types are:

• Dilated cardiomyopathy
• Hypertrophic cardiomyopathy
• Restrictive cardiomyopathy
• Left ventricular non-compaction (LVNC)
• Arrhythmogenic right ventricular dysplasia (ARVD)

Dilated cardiomyopathy is the most common type encountered in childhood. In this condition, the walls of the heart, especially the left ventricle that undertakes the main pumping function, become thinner and the heart expands excessively like a balloon. Since the enlarged heart muscle loses its elasticity and recovery strength, it cannot push the blood filling it into the body strongly enough. The heart, in which blood continuously pools, tries to expand even more to perform its duty, and this situation rapidly exhausts the heart.

Hypertrophic cardiomyopathy is the exact opposite condition. The heart muscle thickens excessively without any apparent reason. The thickened muscle tissue narrows the internal volume of the heart. Even if the heart contracts strongly, the amount of blood pumped to the body decreases significantly because it cannot receive enough blood. In addition, this excessively thick muscle mass may block the outflow tract of blood from the heart, causing the child to suddenly faint or experience chest pain.

Restrictive cardiomyopathy is quite rare, but it is the most difficult type to manage. The walls of the heart muscle become rigid, almost like a hardened sponge or concrete. Although the heart performs its contraction function, because it has stiffened, it cannot stretch and relax sufficiently while filling with blood. Blood accumulates in the upper chambers of the heart (atria), and these chambers reach enormous sizes.

Left ventricular non-compaction disease occurs as a result of the heart muscle not compacting sufficiently during the baby’s development in the womb. While the heart wall should be smooth and even, it remains in a perforated, spongy, and deeply grooved structure. This condition both reduces contraction strength and creates a basis for dangerous blood clots to form between these grooves.

Which Medications Are Used in the Treatment of Cardiac Contraction Disorders in Children?

The main goal of medicine in the treatment of cardiac contraction disorders is not so much to heal the heart as to lighten the excessive load on the heart and give it the opportunity to rest and recover. Forcing a damaged and tired heart to work harder only worsens the condition. Therefore, drug treatments applied in children are based on an extremely delicate balance, and doses are determined with milligram calculations according to the child’s weight.

The drug groups mainly used in treatment are as follows:

• Diuretics
• Beta blockers
• ACE inhibitors
• ARB group drugs
• Positive inotropes
• Aldosterone antagonists

Diuretics, or water pills, are one of the most important cornerstones of heart failure treatment. When the heart cannot pump enough blood, blood flow to the kidneys decreases, and the kidneys think that the body is experiencing dangerous dehydration, so they begin to retain water and salt in the body. This excess fluid leaks into the lungs and abdominal cavity, causing edema. Diuretics stimulate the kidneys, allowing this excess water to be removed through urine. When the unnecessary fluid load in the body decreases, the volume the heart needs to pump decreases and the heart breathes more easily.

Beta blockers are protective shields that protect the heart from harmful stress hormones produced by the body itself (such as adrenaline). When heart failure develops, the body is constantly in a state of alarm and continuously whips the heart to beat faster and stronger. Beta blockers cut these stimulating signals and slow the heart rate. When the heart beats more slowly, it finds much more time to fill with blood and nourish itself between each beat. These drugs allow the heart to rest and prolong its life.

ACE inhibitors and ARB group drugs undertake the task of dilating the vessels. While pumping blood to the body, the heart must overcome the resistance of the vessels. If the vessels are narrowed and constricted, the heart makes a very great effort to overcome this resistance. These drugs relax the vessels and remove the obstacles in front of the heart. Thanks to dilated vessels, blood flows much more easily and the tired heart can perform its duty by spending much less energy.

Which Devices Save Lives in Advanced Stages of Cardiac Contraction Disorders in Children?

In some children, cardiac contraction disorders continue to progress despite all advanced drug treatments given. At this critical point where medications are insufficient to support the heart, engineering marvel medical devices and advanced mechanical support systems come into play and connect children to life. These devices are sometimes a bridge that gives the heart time to recover and sometimes the main element that directly ensures survival.

The main systems used in advanced heart failure are:

• Ventricular assist devices
• Pacemakers
• Implantable cardioverter defibrillators
• Extracorporeal membrane oxygenation
• Artificial heart systems

Ventricular Assist Devices (VAD), popularly known as heart pumps, are tremendous systems that work like the heart’s assistant. When the heart no longer has the strength to pump blood forward, these mechanical pumps placed just outside or inside the chest cavity take over the heart’s task. They take blood from the heart and push it into the body’s main vessels with the help of a powerful motor. These devices specially produced for children can keep the patient safely alive for months or even years until heart transplantation.

Extracorporeal Membrane Oxygenation (ECMO) is generally used in severe myocarditis cases where the heart suddenly fails. This device is a giant life-support machine that undertakes not only the function of the heart but also the lungs. The child’s blood is taken outside the body, enriched with oxygen inside the machine, and pumped back into the body. In this way, the damaged heart can be completely stopped and rested, and invaluable days are gained for the inflammation to pass and the heart to repair itself.

When the heart muscle enlarges and loses its elasticity, the electrical pathways passing through the heart are also damaged. This damage prevents the right and left sides of the heart from contracting in harmony. Pacemakers (CRT) send tiny electrical impulses to different regions of the heart and resynchronize the heart, almost like a skilled orchestra conductor. Thus, the heart muscle begins to work more efficiently and regularly. Implantable Cardioverter Defibrillators (ICD) are smart batteries placed under the skin. When a fatal rhythm disorder develops in the heart, they detect it within seconds and automatically apply an electric shock to return the heart to its normal rhythm, thereby preventing sudden cardiac arrest. At the final point where treatments are insufficient, the most definitive solution is heart transplantation operations.

Are Cardiac Contraction Disorders in Children Genetic and Why Is Family Screening Important?

A large proportion of cardiac contraction disorders grouped under the heading of cardiomyopathies are of genetic origin. These diseases usually occur as a result of subtle errors (mutations) in the genetic codes the child receives from the parents. When genetic transmission is involved, the issue cannot be limited only to treating the child who is currently ill; the entire family must be examined comprehensively. Familial risk management is one of the most fundamental building blocks of pediatric cardiology.

When a cardiac contraction disorder is detected in a child, it is vital for first-degree relatives to undergo regular cardiac check-ups even if they have no complaints. These genetic errors may manifest differently at any age. A disease that appears in infancy in one sibling may be triggered in another sibling during sudden growth spurts in adolescence. Comprehensive genetic tests performed by taking a blood sample create the genetic map of the family and definitively determine which gene is responsible for the disease. In this way, family members at high risk of developing the disease in the future can be protected early, lifestyle changes can be made, and precautions can be taken before dangerous rhythm disorders develop.

Prof. Dr. İbrahim Cansaran TANIDIR

Prof. Dr. İbrahim Cansaran Tanıdır is an internationally recognized specialist with nearly 20 years of clinical, academic, and interventional experience in the fields of congenital heart diseases, pediatric interventional cardiology, hybrid procedures, and radiation-reduced / fluoroscopy-free catheterization techniques.

To date, he has performed more than 10,000 pediatric cardiac catheterization procedures both in Turkey and abroad, and has pioneered advanced interventional and hybrid applications in complex structural heart diseases in our country.

His academic productivity represents a scientifically strong authority with 110 SCI/SCIE publications, 1,440 citations, and an H-index of 18 (Google Scholar, 2025).