Single ventricular heart

Single Ventricle Heart is a congenital heart defect characterized by the presence of only one functional ventricular chamber, which is responsible for pumping blood to both the pulmonary and systemic circulations. This condition is a result of abnormal heart development during fetal life. It encompasses a spectrum of cardiac anomalies, including Hypoplastic Left Heart Syndrome (HLHS), Tricuspid Atresia, and certain forms of Double Outlet Right Ventricle (DORV) and Pulmonary Atresia. Patients with a single ventricle physiology require complex medical management and multiple surgical interventions throughout their lives.

Etiology

The exact cause of single ventricle heart defects is not fully understood, but it is believed to involve a combination of genetic and environmental factors. Genetic mutations and maternal exposure to certain medications or illnesses during pregnancy have been implicated in the development of these conditions.

Pathophysiology

In a normal heart, the right ventricle pumps deoxygenated blood to the lungs, while the left ventricle pumps oxygenated blood to the body. In single ventricle heart conditions, one ventricle is either underdeveloped or absent, leading to the mixing of oxygenated and deoxygenated blood. This results in inefficient blood circulation and the need for the heart to work harder to supply the body with oxygen.

Clinical Manifestations

Symptoms of single ventricle heart defects can vary widely but often include cyanosis (a bluish tint to the skin, lips, and nails), difficulty breathing, poor feeding, and failure to thrive. These symptoms typically present shortly after birth.

Diagnosis

Diagnosis of single ventricle heart defects involves a combination of physical examination, imaging studies such as echocardiography, and sometimes cardiac catheterization. These tests help to define the specific anatomy of the heart, the function of the single ventricle, and the presence of any associated defects.

Treatment

The treatment of single ventricle heart defects is staged and typically involves three surgeries performed over the first few years of life: the Norwood Procedure, the Glenn Procedure, and the Fontan Procedure. These surgeries are designed to reconfigure the heart's circulation to improve oxygen delivery to the body. In some cases, heart transplantation may be considered.

Prognosis

The prognosis for individuals with single ventricle heart defects has improved significantly with advances in surgical techniques and postoperative care. However, long-term outcomes vary, and individuals with this condition require lifelong cardiac care. Complications can include heart rhythm problems, heart failure, and issues related to the Fontan circulation, such as protein-losing enteropathy and liver problems.

Conclusion

Single ventricle heart defects represent a complex group of congenital heart diseases that require a multidisciplinary approach to care. Advances in surgical and medical management have greatly improved survival and quality of life for affected individuals, but challenges remain in the long-term management of these patients.