Cardiac Ablation: Types, Procedure, Benefits, Risks and Recovery

Ablation is a procedure that selectively eliminates the abnormal electrical tissue or congenital accessory pathways responsible for cardiac rhythm disorders (arrhythmias). Ablation therapy is performed by directly targeting the problematic area through thin, flexible tubes called catheters, which are advanced to the heart through the blood vessels in the groin. By correcting irregularities in the heart’s natural electrical system, this method restores a healthy rhythm in a single session and may provide permanent relief without the need for long-term medication. It is one of the most preferred, highly reliable, and modern medical solutions for completely eliminating severe palpitations that significantly reduce quality of life during childhood.

What Is Ablation in the Pediatric Heart and How Does the Electrical System Work?

The heart is not only a muscle that pumps blood but also an extraordinary generator that produces its own electricity. You can think of the human heart as a smart home. This house has main electrical cables and a fuse box that ensure electricity flows regularly between the rooms. In a healthy heart, electrical signals originate from a single center, follow specific pathways, and enable the heart to contract and relax in a regular, coordinated manner.

However, in some children, additional electrical cables (accessory pathways) may be present from fetal development. In other cases, a tiny group of cells within the heart chambers may ignore the main electrical center and begin producing very rapid electrical signals independently. This resembles an electrical short circuit within the house. The heart suddenly starts beating much faster than normal and loses its rhythm. Ablation therapy involves reaching the inside of the heart through very thin, flexible tubes (catheters) inserted from the groin, identifying these short-circuiting accessory pathways or abnormal cell groups, and permanently eliminating them. In this way, the heart’s electrical system is restored to its original factory settings.

What Is Electrophysiological Mapping Performed Before Deciding on Ablation?

Before treating a heart rhythm disorder, it is necessary to know exactly where the problem is located. Just as repairs cannot begin without locating a short circuit in a house, ablation is not performed before the exact location of the problem within the heart is identified. Electrocardiography (ECG), performed using electrodes attached to the chest, or Holter monitoring, which records heart rhythm for twenty-four hours, can demonstrate the presence of a rhythm disorder but cannot always pinpoint the exact location within the heart.

An electrophysiological study is a direct mapping procedure performed from inside the heart. Very thin catheters are placed in different chambers of the heart, and the heart’s real-time electrical signals are transmitted to large computer screens. This stage is entirely dedicated to identifying and locating the source of the problem. During the procedure, physicians deliver small electrical impulses to the heart to deliberately reproduce the patient’s arrhythmia under controlled laboratory conditions. Once the arrhythmia begins, the electrical signals displayed on the monitors are analyzed, and the exact source of the problem is identified. After the abnormal area has been located through mapping, the procedure continues seamlessly into the treatment phase, namely catheter ablation.

Which Symptoms of Heart Rhythm Disorders Indicate the Need for Ablation?

Normal heart rate in children varies considerably depending on age. It is entirely physiological and normal for a newborn’s heart to beat between one hundred and one hundred sixty times per minute. As children grow, the heart enlarges and the heart rate gradually slows. During the preschool years, the rate decreases to approximately ninety to one hundred forty beats per minute, while during adolescence it reaches the adult range of sixty to one hundred beats per minute.

If a school-aged child’s heart suddenly exceeds one hundred sixty or even two hundred beats per minute while resting, watching television, or sleeping, this may indicate a significant heart rhythm disorder requiring attention. Such sudden episodes, in which the heart feels as though it is fluttering like a bird, can greatly reduce a child’s quality of life.

The main symptoms of heart rhythm disorders in children include:

• Sudden onset of palpitations
• Unexplained fatigue
• Chest pain
• Dizziness
• Temporary loss of vision or blackout
• Fainting
• Shortness of breath

In the past, children experiencing these symptoms were often prescribed antiarrhythmic medications for many years. However, long-term use of powerful cardiac medications in a growing child may produce undesirable effects. Furthermore, these medications are effective only while being taken and do not permanently eliminate the underlying problem. For these reasons, interventional treatments that provide permanent relief have become increasingly preferred.

The main rhythm disorders requiring ablation include:

• Supraventricular tachycardia (AVRT, AVNRT)
• Wolff-Parkinson-White syndrome (WPW)
• Atrial flutter
• Ectopic atrial tachycardia
• Focal atrial tachycardia
• Ventricular tachycardia

Which Energy Sources Are Preferred for Ablation Procedures in Children?

The type of energy used to eliminate tiny abnormal electrical foci within the heart is one of the most important factors determining both the long-term success of the procedure and patient safety. Thanks to advances in medical technology, physicians are no longer limited to a single technique, and different options can be selected according to the location of the arrhythmia and the patient’s anatomy.

Modern pediatric cardiology centers generally use three main energy modalities. The first is conventional radiofrequency energy, which destroys tissue through controlled heat. The second is cryoablation technology, which suppresses abnormal cells by freezing them to extremely low temperatures. The third and newest approach is electroporation, which works entirely at the cellular level without using either heat or cold. Each technique has a completely different application method and biological effect on cardiac tissue.

How Is Radiofrequency Ablation Performed?

Radiofrequency ablation is the oldest and most well-established technique in clinical practice. The tip of a specially designed catheter is brought into contact with the tissue responsible for the rhythm disorder. High-frequency radio wave energy is then delivered through the catheter tip. This energy creates controlled heating of approximately fifty to seventy degrees Celsius in the contacted tissue.

The heated cells undergo structural changes and permanently lose their ability to conduct electrical signals. As a result, electrical short circuits can no longer occur in that region. Radiofrequency ablation has a very high success rate, and the abnormal focus can often be permanently eliminated with a single application. However, there are situations in which this method must be applied with particular caution in children. If the accessory electrical pathway requiring treatment is located very close to the heart’s main conduction center (the atrioventricular node), there is a possibility that heat may spread to this healthy area. Damage to this vital conduction center may permanently interrupt the heart’s electrical system. Such a complication could require the child to live with a permanent pacemaker for the rest of life. For this reason, alternative and safer energy sources have been developed for procedures involving these critical regions.

Why Is Cryoablation, Also Known as the Freezing Technique, Important?

Cryoablation works by freezing tissue instead of heating it. Special cooling gases are delivered to the catheter tip, allowing the contacted tissue to be frozen to approximately minus eighty degrees Celsius. This extreme cold causes the abnormal cells to freeze completely and lose their function. The reason cryoablation has become such a revolutionary and indispensable technique in pediatric cardiology is that freezing can be performed gradually and allows a reversible safety test.

This safety test is called cryomapping. Instead of immediately freezing the tissue to minus eighty degrees Celsius, physicians first cool the target tissue gradually to approximately minus thirty degrees Celsius. At this temperature, electrical conduction is temporarily interrupted without causing permanent cellular damage. During this stage, physicians carefully evaluate whether the heart’s normal conduction pathways have been affected. If any undesirable effect is observed, such as interruption of normal conduction, freezing is immediately stopped. Within seconds, the catheter warms up, the tissue returns to its healthy state, and no permanent damage occurs. However, if testing at minus thirty degrees confirms that only the abnormal pathway has been suppressed, the temperature is safely lowered to minus eighty degrees, completing the procedure permanently. This remarkable feature virtually eliminates the risk of requiring a permanent pacemaker.

What Are the Advantages of Ablation Therapy Using the New-Generation Electroporation Method?

This technique, known as Pulsed Field Ablation or electroporation, represents one of the newest and most exciting developments in interventional cardiology. Unlike conventional techniques, it is based on neither heating nor freezing. Instead, it is a completely non-thermal approach. When the catheter contacts the abnormal tissue, specially calibrated, extremely high-voltage electrical pulses lasting only millionths of a second are delivered.

The biological effect of these pulses is remarkably selective. The electrical current affects only cardiac muscle cells by creating permanent microscopic pores in their cell membranes. Through these pores, the abnormal rhythm-producing cells die. Perhaps the most remarkable feature is that surrounding tissues remain completely unharmed. The esophagus located immediately behind the heart, the phrenic nerves responsible for breathing, and the delicate coronary arteries supplying the heart are naturally resistant to these electrical pulses. By selectively eliminating only diseased cardiac tissue while preserving surrounding vital structures, this technology provides an excellent safety profile.

Although this new technology is widely used in adults for atrial fibrillation, its application in children is only beginning to expand.

How Is Radiation-Free Ablation Performed Using Three-Dimensional Mapping Systems?

In previous years, fluoroscopy, which continuously emits X-rays, was routinely used to visualize catheters inside the heart and monitor their movement during the procedure. As procedure time increased, so did radiation exposure. Because children’s tissues and cells are rapidly developing, they are considerably more sensitive to radiation than adults. Protecting children from the cumulative and long-term cellular effects of radiation has therefore become a major priority in modern medicine.

To solve this problem, three-dimensional electroanatomical mapping systems are now widely used. Intelligent sensor pads are placed on the child’s chest, back, and legs. Special catheters advanced into the heart continuously transmit information to the computer through magnetic fields and sensitive sensors. Like a GPS navigation system, this technology displays the catheter’s exact location within the heart with millimetric precision. As the physician moves the catheter, a real-time, colorful, three-dimensional model of the heart is gradually created on the monitor. The site where the arrhythmia originates appears as a bright red focal point on this map. The physician identifies the abnormal area, performs the ablation, and completes the procedure successfully. In this way, the entire procedure can be completed safely without using X-ray radiation even for a single second.

Which Blood Vessels and Equipment Are Used During an Ablation Procedure?

Access to the heart requires an entry route, and these are usually the large veins located in the legs. Since children’s vessel sizes vary considerably according to age and body weight, the equipment must be selected very carefully. Using equipment that is too large may cause vascular injury or bleeding.

The right femoral vein in the groin is generally the preferred access site. When necessary, the left groin or, very rarely, veins in the neck may also be used. In infants weighing less than five kilograms, extremely fine, millimeter-sized vascular access sets are used. Slightly larger equipment is used in preschool-aged children, whereas standard adult-sized flexible sheaths can safely be used in older children and adolescents. Selecting equipment that precisely matches the patient’s size is one of the fundamental requirements for a successful procedure.

What Are the Success Rates and Possible Risks of Ablation Therapy?

When performed in technologically advanced centers by experienced specialists, ablation has an exceptionally high success rate. In supraventricular tachycardias, commonly described as electrical short circuits, complete elimination of the condition in a single session exceeds 90–95%. In some more resistant rhythm disorders, success rates generally range from 80% to 90%. In children with congenital heart defects or previous open-heart surgery, where complex arrhythmias arise from surgical scar tissue, success rates may be somewhat lower, and repeat procedures may become necessary in subsequent years.

Every medical procedure carries certain potential risks. Although ablation is considered highly safe, it remains an invasive procedure involving entry into the body. Serious permanent or life-threatening complications occur at very low rates of approximately one to two percent.

Very rare risks that may occur during an ablation procedure include:

• Bruising in the groin
• Mild bleeding
• Fluid accumulation around the heart
• Permanent slowing of the heart rhythm
• Blood clot formation

Throughout the procedure, anticoagulant medications are administered, vascular access is obtained carefully under ultrasound guidance, and three-dimensional mapping systems are used to minimize the likelihood of these complications.

What Preparations Are Made Before an Ablation Procedure in the Hospital?

This process requires both the child and family to be prepared psychologically and physically through a multidisciplinary approach. Above all, any antiarrhythmic medications or syrups the patient is taking must be discontinued for the number of days specified by the physician before the procedure. If these medications are continued, they may suppress the arrhythmia during the procedure, making it impossible to identify the abnormal electrical focus.

On the day of admission, comprehensive blood tests are performed, a current ECG is obtained, and the structural condition of the heart is evaluated one final time using echocardiography. To ensure that children experience no fear, pain, or movement during the procedure, ablation is performed under general anesthesia or deep sedation. During anesthesia, an empty stomach is critically important. If the stomach is full, food may enter the airway and lungs while the child is asleep. To eliminate this risk completely, children must not eat or drink anything, including water, for six to eight hours before the procedure, depending on their age.

What Is the First Twenty-Four-Hour Follow-Up Period Like After Ablation?

After the procedure has been successfully completed and the abnormal rhythm-producing tissue has been eliminated, the catheters are removed from the body. Firm manual pressure is applied to the vascular entry site in the groin until bleeding stops completely, followed by the application of a tight bandage. The patient is then gradually awakened and transferred first to the recovery area and then to the hospital room.

These first few hours require patience but are extremely important. To allow the large vein in the groin to heal properly and eliminate the risk of bleeding, the child is instructed to remain lying flat on the back without bending the leg for four to six hours. If necessary, a small sandbag may be placed over the area for additional support. Nurses regularly monitor the child’s pulse, blood pressure, toe temperature, and groin access site.

Contrast agents may occasionally be administered during the procedure to improve visualization of the heart. To facilitate rapid elimination of these substances through the kidneys, children are encouraged to drink plenty of water once they are awake and able to eat. During the first day, heart rhythm is continuously monitored using bedside monitors. If no complications occur, most patients remain in the hospital for only one night and are discharged home the following morning after their final evaluation.

What Should Be Considered During Recovery After Discharge Following Ablation?

Although families feel relieved once they return home, both the heart and the small vascular access site in the groin require a little more time to heal completely. During the first few days after discharge, children are generally advised to stay home from school and rest quietly. The tight bandages over the groin are usually removed at the end of the first day after discharge. Once the bandages have been removed, there is no medical reason to prevent the child from taking a short shower with warm—not hot—water while standing. However, care should be taken to keep the groin puncture sites clean until they have completely healed to reduce the risk of infection.

Activities that should be avoided during the first two weeks after discharge include:

• Lifting heavy objects
• Climbing stairs quickly
• Running
• Taking baths in a bathtub
• Swimming in the sea
• Swimming in a pool

Because ablation deliberately creates a very small controlled area of injury within the heart, temporary swelling and a natural inflammatory healing response occur at the treated site. During this healing period, it is completely normal for children to occasionally feel skipped heartbeats or experience brief, mild palpitations during the first few weeks. As the heart gradually adapts to its new healthy rhythm, these minor symptoms usually disappear on their own over the following weeks.

Which Emergency Situations Require Medical Attention After Ablation?

To evaluate the long-term success of ablation, confirm that recovery is progressing well, and verify the heart’s new rhythm, an outpatient follow-up visit is usually scheduled one to three months after discharge. During this visit, an ECG is performed, a 24-hour Holter monitor may be used if necessary, and, if everything is normal, the patient is generally allowed to resume all normal activities without restrictions.

However, several uncommon but important warning signs require immediate medical evaluation during recovery at home. If any of these occur, families should seek medical attention without waiting for the routine follow-up appointment.

Emergency situations requiring immediate medical attention include:

• Severe chest pain
• Severe shortness of breath
• High fever
• Sudden swelling in the groin
• Drainage from the groin
• Recurrent fainting

Frequently Asked Questions

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).