Pulmonalstenos

Pulmonalstenos, also known as pulmonary stenosis, is a narrowing of the right ventricular outflow tract that impedes blood flow from the right ventricle to the pulmonary artery. It is most commonly a congenital condition but can be acquired later in life. The narrowing may occur at the level of the pulmonary valve (valvular stenosis), below the valve (subvalvular or infundibular stenosis), or above the valve (supravalvular stenosis).

Pathophysiology and presentation often depend on the degree and location of obstruction. The obstruction increases right ventricular afterload, which can lead to right ventricular hypertrophy and, in severe cases, right heart failure. The clinical picture ranges from asymptomatic to exertional dyspnea, fatigue, chest pain, or syncope. A systolic ejection murmur is commonly heard, typically best at the left upper sternal border, and may be accompanied by a variable second heart sound.

Diagnosis relies on imaging and hemodynamics. Echocardiography is the primary tool, allowing anatomical assessment and measurement of the pressure gradient across the lesion. Electrocardiography may show signs of right ventricular hypertrophy. Additional imaging such as cardiac magnetic resonance or computed tomography can delineate anatomy, and cardiac catheterization may be used to obtain precise gradient measurements.

Treatment depends on severity and symptoms. Mild cases may require observation. Significant stenosis or symptomatic cases are often treated with percutaneous balloon valvuloplasty for valvular stenosis or surgical relief for subvalvular or complex forms. Neonates with critical pulmonalstenos may need prostaglandin E1 to maintain ductal flow prior to intervention. Long-term prognosis is generally favorable with proper treatment, though residual stenosis or pulmonary regurgitation can occur, necessitating ongoing follow-up. Pulmonalstenos may be associated with other congenital heart defects, such as Tetralogy of Fallot.