Transposition of the Great Arteries 

Diagnosis  

Transposition of the great arteries is typically identified after a baby is born, but occasionally it can be detected before birth through a routine pregnancy ultrasound. In such cases, a fetal echocardiogram may be performed to confirm the diagnosis by examining the unborn baby’s heart. After birth, healthcare professionals may consider the possibility of TGA if the baby exhibits symptoms such as bluish or pale skin, a weak pulse, or difficulties with breathing. During a physical examination, the healthcare provider may also detect a heart sound known as a murmur when listening to the baby’s heart. 

Confirmation of a diagnosis of transposition of the great arteries may require several tests, including: 

• Echocardiogram. This procedure utilizes sound waves to generate dynamic images of the pulsating heart. It visually demonstrates the movement of blood within the heart, including its flow through the heart valves and blood vessels. Additionally, it can provide insight into the locations of the primary arteries exiting the heart. Furthermore, an echocardiogram has the capability to identify congenital heart abnormalities like a cardiac septal defect. 
• Chest X–ray. A chest X–ray provides information about the heart and lungs, but it is not sufficient to diagnose TGA. However, it does assist healthcare providers in assessing the size of the heart. 
• Electrocardiogram (ECG or EKG). A simple and painless test is used to measure the electrical activity of the heart. The test involves placing sticky patches called electrodes on the chest, and sometimes on the arms and legs. These electrodes are connected to a computer with wires, which displays the results of the test. By examining the results, a doctor can determine if the heart is beating too fast, too slow, or not beating at all. 
• Pulse oximetry screening: pulse oximetry screening for newborns is a common procedure used to assess oxygen levels as part of their routine care. 

Treatment

Surgical intervention is necessary to correct the heart problem in all infants diagnosed with complete transposition of the great arteries (D–TGA). However, the treatment approach for congenitally corrected transposition (L–TGA) varies depending on the timing of diagnosis and the presence of any additional heart conditions. 

Medicines

Before performing surgery to correct the switched arteries, doctors may administer a medication called alprostadil. This medication enhances blood flow and promotes improved mixing of oxygen–poor and oxygen–rich blood. 

Surgery

Treatment options for TGA vary depending on the specific type of TGA. While not all individuals with congenitally corrected transposition require surgery, it is typically recommended for most cases. Surgical interventions and other treatments for TGA may include: 

• Atrial septostomy: This is a procedure that can be performed as an immediate, short–term solution prior to surgery. It involves the use of slender tubes and small incisions to expand a natural connection between the upper chambers of the heart. This process facilitates the mixing of oxygen–rich and oxygen–poor blood, leading to improved oxygen levels within the baby’s body. 
• Arterial switch operation: The arterial switch operation is a frequently performed surgical procedure for correcting transposition of the great arteries, which is a common congenital heart defect. In this surgery, the two primary arteries that exit the heart are repositioned to their appropriate locations. Other heart problems present at birth may be repaired during this surgery. 
• Atrial switch operation: During the surgery, the surgeon divides the blood flow between the two upper chambers of the heart. As a result, the right lower chamber of the heart now needs to pump blood not only to the lungs but also to the rest of the body. 
• Rastelli procedure: In some cases, when a baby has a heart condition called TGA and also has a hole in the heart known as a ventricular septal defect, a surgery may be performed. During this surgery, the surgeon closes the hole and changes the way blood flows in the heart. This allows oxygen–rich blood to reach the body. They use an artificial valve to connect one part of the heart to an artery leading to the lungs. 
• Double switch procedure: The goal of the surgery is to change the way blood flows into the heart. By rearranging the connections of the major arteries, the surgery allows the lower left chamber of the heart to pump oxygen–rich blood to the body’s main artery, called the aorta.
• Pacemaker: If TGA produces slow heartbeats, a pacemaker device may be advised. This is usually associated with the closure of the VSD.