TAPVR

Total Anomalous Pulmonary Venous Return (TAPVR) is a rare congenital heart defect in which all four pulmonary veins do not connect normally to the left atrium. Instead, the pulmonary veins drain abnormally to the right atrium or to a systemic vein, which leads to the mixing of oxygenated and deoxygenated blood. This condition is present at birth and affects the efficiency of the heart's ability to pump oxygen-rich blood to the body.

Classification

TAPVR is classified into four types based on the site where the pulmonary veins drain:

• Type I (Supracardiac): The most common type, where the pulmonary veins drain to the right atrium via a systemic vein such as the innominate vein.
• Type II (Cardiac): The pulmonary veins drain directly into the right atrium or into the coronary sinus.
• Type III (Infracardiac): The pulmonary veins drain into the portal vein, hepatic vein, or ductus venosus.
• Type IV (Mixed): A combination of the above types, where the pulmonary veins drain into more than one site.

Symptoms and Diagnosis

Infants with TAPVR may exhibit symptoms shortly after birth, including rapid breathing, bluish skin coloration (cyanosis), poor feeding, and lethargy. The diagnosis of TAPVR is often made using echocardiography, which can visualize the abnormal connections. Other diagnostic tools may include cardiac MRI and cardiac catheterization.

Treatment

Surgical correction is the only effective treatment for TAPVR. The surgery involves creating a connection between the pulmonary veins and the left atrium, while also closing off any abnormal connections to the right atrium or systemic veins. The timing of surgery is crucial and is usually performed early in life, often within the first few weeks or months after birth, depending on the severity of the condition and the presence of other heart defects.

Prognosis

The prognosis for children with TAPVR following surgery is generally good, with many leading normal lives. However, the outcome can vary depending on the type of TAPVR, the presence of associated cardiac defects, and the timing of the surgery. Complications can include pulmonary venous obstruction, arrhythmias, and the need for reoperation.

Epidemiology

TAPVR is a rare condition, accounting for about 1-2% of all congenital heart defects. It occurs equally in males and females and has no known specific risk factors, although genetic and environmental components may play a role.