Single ventricle

Single Ventricle Single ventricle is a rare congenital heart defect where one of the heart's ventricles is underdeveloped or absent. This condition affects the normal flow of blood through the heart and requires complex medical management and surgical interventions.

Anatomy and Physiology

In a normal heart, there are four chambers: two atria and two ventricles. The ventricles are responsible for pumping blood to the lungs and the rest of the body. In single ventricle defects, one of these ventricles is either missing or severely underdeveloped, leading to a range of physiological challenges.

Types of Single Ventricle Defects

There are several types of single ventricle defects, including:

• Hypoplastic Left Heart Syndrome (HLHS): The left side of the heart is underdeveloped.
• Tricuspid Atresia: The tricuspid valve is missing or abnormally developed, affecting the right ventricle.
• Double Inlet Left Ventricle (DILV): Both atria connect to the left ventricle, with the right ventricle being underdeveloped.

Diagnosis

Diagnosis of single ventricle defects typically occurs through prenatal ultrasound or shortly after birth. Echocardiography is the primary tool used to assess the structure and function of the heart.

Treatment

Treatment for single ventricle defects often involves a series of surgeries aimed at redirecting blood flow to compensate for the missing or underdeveloped ventricle.

Surgical Interventions

• Norwood Procedure: The first stage surgery, usually performed shortly after birth, to create a new aorta and connect it to the right ventricle.
• Glenn Procedure: The second stage surgery, typically performed at 4-6 months of age, connects the superior vena cava to the pulmonary arteries.
• Fontan Procedure: The final stage surgery, performed at 2-4 years of age, connects the inferior vena cava to the pulmonary arteries, completing the separation of oxygenated and deoxygenated blood.

Prognosis

The prognosis for individuals with single ventricle defects varies depending on the specific type of defect and the success of surgical interventions. Lifelong follow-up with a cardiologist is essential.

Complications

Potential complications include heart failure, arrhythmias, and issues related to the Fontan circulation, such as protein-losing enteropathy.

Research and Future Directions

Ongoing research aims to improve surgical techniques, develop better management strategies, and explore the potential for regenerative therapies.

See Also

• Congenital heart defect
• Hypoplastic Left Heart Syndrome
• Tricuspid Atresia
• "Single Ventricle Defects." American Heart Association. Accessed October 2023.
• "Congenital Heart Defects." National Heart, Lung, and Blood Institute. Accessed October 2023.

NIH genetic and rare disease info

• NIH info on Single ventricle

Single ventricle is a rare disease.