Taussig–Bing Syndrome

Overview

Taussig–Bing syndrome is a rare and complex congenital heart defect that falls under the category of cyanotic congenital heart disease. It is a variant of double outlet right ventricle (DORV), where both the aorta and pulmonary artery arise from the right ventricle. The defining feature of Taussig–Bing syndrome is the presence of a subpulmonic ventricular septal defect (VSD), which allows oxygenated blood from the left ventricle to pass preferentially into the pulmonary artery. This anatomical arrangement causes physiological effects similar to transposition of the great arteries (TGA), leading to significant mixing of oxygenated and deoxygenated blood, and resulting in cyanosis. The condition is named after Drs. Helen B. Taussig and Richard Bing, who first described it in 1949.

Causes

Taussig–Bing syndrome arises during embryonic development due to abnormal cardiac looping and septation. The exact causes are not fully understood, but several contributing factors have been identified:

• Genetic factors – Some cases are associated with chromosomal abnormalities or genetic syndromes such as 22q11.2 deletion syndrome (DiGeorge syndrome).

• Sporadic mutations – In many cases, the condition occurs without a clear hereditary pattern and is thought to result from spontaneous mutations or developmental errors during early fetal growth.

• Environmental influences – Maternal conditions like diabetes or exposure to teratogens during pregnancy may increase the risk of congenital heart defects, though no specific cause has been conclusively linked to Taussig–Bing syndrome.

Symptoms

The clinical presentation of Taussig–Bing syndrome typically begins shortly after birth and reflects impaired oxygenation of the blood. Common signs and symptoms include:

• Cyanosis – Bluish discoloration of the skin, lips, and nail beds due to reduced oxygen saturation.

• Tachypnea – Rapid breathing, especially during feeding or exertion.

• Poor feeding – Infants may have difficulty feeding and show signs of fatigue.

• Failure to thrive – Delayed weight gain and growth due to chronic hypoxia and energy expenditure.

• Heart murmur – A characteristic sound heard on auscultation due to turbulent blood flow through the VSD or outflow tracts.

• Signs of congestive heart failure – Including hepatomegaly, sweating, and poor perfusion in severe cases.

Without surgical intervention, the condition typically leads to progressive heart failure and death in early infancy.

Diagnosis

Diagnosing Taussig–Bing syndrome requires a combination of clinical assessment and advanced imaging techniques. Key diagnostic methods include:

• Physical examination – Identification of cyanosis, abnormal heart sounds, and signs of heart failure.

• Pulse oximetry – Low oxygen saturation in a newborn suggests cyanotic congenital heart disease.

• Echocardiography – The primary imaging tool that visualizes the heart's anatomy and confirms the presence of double outlet right ventricle, the location of the VSD, and the relationship of the great arteries.

• Cardiac MRI or CT angiography – Provides detailed anatomical information for surgical planning.

• Cardiac catheterization – Occasionally used to assess pressures, oxygen saturations, and to confirm complex anatomy when non-invasive imaging is inconclusive.

• Genetic testing – May be performed to rule out syndromic associations, especially in patients with other anomalies.

Treatment

Treatment of Taussig–Bing syndrome is surgical and must be tailored to the patient’s specific cardiac anatomy. Medical therapy may be used to stabilize the infant before surgery. Key treatment strategies include:

Preoperative Management

• Prostaglandin E1 infusion – Used to keep the ductus arteriosus open in some cases to improve oxygenation.

• Diuretics and inotropes – To manage symptoms of congestive heart failure while preparing for surgery.

Surgical Options

• Arterial switch operation (ASO) – Often combined with VSD closure and used if the great vessels are arranged as in TGA (transposition-like physiology).

• Intraventricular tunnel repair (Rastelli procedure) – Used when a conduit is required to redirect blood flow from the left ventricle to the aorta and from the right ventricle to the pulmonary artery.

• Alternative surgeries – Depending on the complexity of the heart defect and the presence of associated anomalies.

Surgical correction is typically performed within the first few months of life to prevent irreversible damage to the heart and lungs.

Prognosis

With timely surgical intervention and appropriate postoperative care, the prognosis for infants with Taussig–Bing syndrome has significantly improved in recent decades. Key prognostic factors include:

• Timing of surgery – Early correction yields better outcomes and reduces the risk of complications.

• Complexity of cardiac anatomy – Patients with additional cardiac or extracardiac anomalies may have a more guarded prognosis.

• Surgical expertise and follow-up – Successful long-term outcomes depend on high-quality pediatric cardiac surgery and ongoing cardiology care.

Many children who undergo corrective surgery go on to lead healthy lives, though they often require lifelong cardiology monitoring and, in some cases, further interventions as they grow.