What Is Transposition of the Great Arteries? Transposition of the great arteries (TGA) is a congenital heart disease in which the two main arteries leaving the heart are connected to different ventricles than normal. In a normal heart, the aorta leaves the left ventricle and carries oxygen-rich blood to the body. The pulmonary artery leaves the right ventricle and sends oxygen-poor blood to the lungs. In transposition of the great arteries, particularly in the type known as complete transposition, d-TGA, these connections are reversed. The aorta arises from the right ventricle, and the pulmonary artery arises from the left ventricle. For this reason, the body and lung circulations become two separate parallel circulations. For the baby to survive, oxygenated and unoxygenated blood must mix through openings within the heart or vascular connections. Transposition of the great arteries is a critical heart disease that requires urgent evaluation in the newborn period and, in most cases, early surgical treatment. Why Does Transposition of the Great Arteries Occur? The disease arises during the baby's heart development in the womb. The exact cause is unknown in most cases. Some genetic and environmental factors are thought to play a role. Transposition of the great arteries may occur on its own or together with other heart anomalies such as ventricular septal defect (VSD) and pulmonary outflow tract obstruction. What Are the Symptoms of Transposition of the Great Arteries? Symptoms usually appear in the first hours or days after birth. The most common symptoms are: - Marked bluish discoloration of the lips and skin - Low blood oxygen levels - Rapid breathing - Feeding difficulty - Tiring quickly - Weakness - Circulatory disturbance in severe cases - Changes in consciousness in advanced cases Bluish discoloration that appears right after birth and continues despite oxygen support may be a sign of serious congenital heart disease. In this case, urgent pediatric cardiology evaluation is required. How Is Transposition of the Great Arteries Diagnosed? Transposition of the great arteries can be diagnosed in some babies during pregnancy with fetal echocardiography. Prenatal diagnosis helps in planning for the baby to be born at a center with pediatric cardiology, pediatric heart surgery, and neonatal intensive care facilities. The main diagnostic methods used after birth are: 1. Echocardiography (ECHO) This is the basic diagnostic method that evaluates the connections of the great vessels leaving the heart, the openings within the heart, and blood flow. 2. Oxygen Saturation Measurement The oxygen level in the baby's blood is checked. 3. Electrocardiography (ECG) Heart rhythm and electrical activity are examined. 4. Chest X-Ray It can provide helpful information about heart size and lung circulation. 5. Cardiac CT or MRI It may be used in selected patients in whom the complex vascular anatomy needs to be evaluated in detail. How Is Initial Treatment Carried Out in Transposition of the Great Arteries? In diagnosed newborns, the first aim is to stabilize the baby's circulation by ensuring adequate mixing of oxygenated and unoxygenated blood. Intensive care support and some interventional procedures may be required in this process. Prostaglandin E1 Treatment It may be given to keep open the vascular connection called the ductus arteriosus. In some babies, this connection helps increase the mixing of blood between the two circulations. Balloon Atrial Septostomy Balloon atrial septostomy may be performed in babies in whom the opening between the atria is inadequate. In this procedure, the opening between the atria is enlarged with the help of a catheter so that blood mixes better. Balloon atrial septostomy may be performed to improve the baby's oxygenation before definitive surgical treatment. Is Surgery Necessary in Transposition of the Great Arteries? Surgical treatment is generally necessary in complete transposition of the great arteries. Today, in newborns with suitable anatomical features, the standard corrective surgical method is the arterial switch operation. With this operation, the aorta and pulmonary artery are connected to the correct ventricles. In addition, the coronary vessels that supply the heart must also be moved to the new aortic root. The aim of surgical treatment is to re-establish normal series circulation so that oxygen-rich blood reaches the body. What Is the Arterial Switch Operation? The arterial switch operation is the anatomical corrective surgical method used in transposition of the great arteries. During this procedure: 1. The aorta and pulmonary artery are separated at appropriate levels. 2. The aorta is reconnected so that it arises from the left ventricle. 3. The pulmonary artery is arranged so that it arises from the right ventricle. 4. The coronary arteries are moved to the new aortic root. 5. The vascular connections and blood flow are checked. The operation is performed with heart-lung machine support. With this method, the aim is to create a structure close to the normal circulatory arrangement of the heart. When Is the Arterial Switch Operation Performed? The arterial switch operation is usually performed in the first days or within the first few weeks after birth. Early surgery is preferred especially in simple d-TGA cases in which there is no opening between the ventricles within the heart. The reason is that after birth, the capacity of the left ventricle to support the high-pressure systemic circulation may decrease over time. However, the exact timing of the operation is determined according to the baby's clinical condition, heart anatomy, and accompanying anomalies. Is the Same Operation Performed on Every Child with Transposition of the Great Arteries? The same surgical method is not used in every child. Different surgical approaches may be required in some patients, particularly those with a large VSD, severe pulmonary stenosis, or complex coronary vessel anatomy. In selected complex cases, different corrective operations such as Rastelli, Nikaidoh, or REV may be considered. In addition, ccTGA, known as congenitally corrected transposition, is a different disease from complete transposition, and its surgical approach may differ. For this reason, accurate anatomical diagnosis and individualized surgical planning are of great importance. Is the Arterial Switch Operation Risky? The arterial switch operation is one of the important and complex heart operations performed in the newborn period. Surgical risks vary according to the baby's weight, general health, coronary vessel anatomy, and accompanying heart anomalies. Possible complications include: - Bleeding and infection - Heart rhythm disorders - Deterioration of heart function - Circulatory problems related to the coronary vessels - Narrowing at the pulmonary artery connections - Leakage of the new aortic valve - The need for additional surgery or a catheter procedure It is important for the operation to be performed at experienced pediatric heart surgery centers. Intensive Care Process After Surgery After the arterial switch operation, babies are closely monitored in the pediatric heart surgery intensive care unit. During this period, heart function, blood pressure, breathing, and oxygen level are continuously evaluated. During the intensive care process: - Heart rhythm is monitored. - Circulation and blood supply to the organs are checked. - The need for respiratory support is evaluated. - Coronary circulation and heart function are followed. - Fluid balance is regulated. - A feeding plan is created. The length of stay in intensive care may vary according to the baby's general health and the speed of recovery after surgery. How Long Does Recovery Take After Great Artery Surgery? The recovery period is different for every baby. In cases that progress without complications, the hospital stay may be shorter, while longer follow-up may be needed in complex heart anomalies. After discharge, families are given information about medication use, feeding, wound care, and follow-up examinations. Monitoring the baby's weight gain, growth, and heart function is especially important in the first months. Can Children Live Normally After the Arterial Switch Operation? After a successful arterial switch operation, many children can show normal growth and development. Children can continue school life and take part in physical activities in line with the cardiology specialist's evaluation. However, in later years, some patients may develop pulmonary artery narrowing, enlargement of the new aortic root, aortic valve insufficiency, or coronary vessel problems. For this reason, regular cardiac follow-up is necessary even if the operation is successful. Why Is Long-Term Follow-Up Important After Surgery? The long-term heart health of children who have had surgery for transposition of the great arteries should be evaluated regularly. At check-ups: Echocardiography (ECHO): Heart function, valves, and the connections of the great vessels are examined. Electrocardiography (ECG): Heart rhythm is evaluated. Cardiac MRI or CT: The great vessels and coronary arteries are imaged in detail when necessary. Exercise Tests: In children of suitable age, physical capacity and the heart's response to exercise can be evaluated. In individuals with congenital heart disease, it is also important to continue specialist cardiology follow-up during the transition from childhood to adulthood. Why Are Early Diagnosis and Correct Surgical Timing Vital? Transposition of the great arteries is a critical heart disease that can cause severe oxygen deficiency right after birth. Diagnosis during pregnancy helps in planning the birth at a suitable center and preparing the necessary treatment team. Rapid evaluation after birth, necessary intensive care support, and surgical intervention performed on time can increase the baby's chance of survival. Remember: Transposition of the great arteries is a serious congenital heart disease that requires early diagnosis and appropriate surgical treatment. Thanks to the arterial switch operation, near-normal blood circulation can be achieved in many children. Correct surgical timing, an experienced specialist team, and lifelong cardiology follow-up are of great importance for children's long-term heart health and quality of life.