Subpulmonary stenosis

Subpulmonary stenosis, also known as infundibular pulmonary stenosis or subvalvular pulmonary stenosis, is a congenital heart defect characterized by narrowing (stenosis) of the right ventricular outflow tract below the pulmonary valve. This obstruction occurs in the infundibular region of the right ventricle, where muscular or fibrous tissue creates a barrier to blood flow from the right ventricle to the pulmonary artery. The condition primarily affects the cardiovascular system and can occur as an isolated defect or in association with other congenital heart malformations, most notably tetralogy of Fallot. Patients with subpulmonary stenosis may present with symptoms ranging from mild to severe depending on the degree of obstruction. Key clinical features include a cardiac murmur (typically a systolic ejection murmur heard at the left upper sternal border), exertional dyspnea (shortness of breath during physical activity), fatigue, and in severe cases, cyanosis (bluish discoloration of the skin due to reduced oxygen levels). Right ventricular hypertrophy may develop over time as the heart works harder to pump blood through the narrowed outflow tract. In neonates and infants with severe obstruction, symptoms may include failure to thrive and signs of right heart failure. Diagnosis is typically made through echocardiography, which can visualize the site and severity of the obstruction, supplemented by cardiac catheterization in some cases. Treatment depends on the severity of the stenosis. Mild cases may require only monitoring, while moderate to severe cases often necessitate surgical intervention. Surgical resection of the obstructing infundibular muscle or fibrous tissue is the primary treatment approach. In some cases, balloon dilation or placement of a transannular patch may be required. Outcomes following surgical correction are generally favorable, particularly when the condition is identified and treated early.

Common questions about Subpulmonary stenosis