Subpulmonary

Subpulmonary is an anatomical term used in anatomy and cardiology to describe a position beneath the pulmonary valve. It is commonly applied to describe structures or lesions that lie in the right ventricular outflow tract just distal to the pulmonary valve, or defects that involve the region immediately below the valve.

In clinical use the term frequently appears in reference to subpulmonic or subpulmonic stenosis, a form of right ventricular outflow tract obstruction. The obstruction is located below the pulmonary valve and can involve the infundibulum or tissues just beneath the valve, reducing blood flow to the pulmonary artery and increasing right ventricular pressure.

Subpulmonary stenosis is encountered in various congenital heart diseases and is a recognized component of conditions such as tetralogy of Fallot. It may also be present with other defects that affect the subpulmonic region. Distinguishing subpulmonary lesions from supravalvular (above the valve) or valvular (at the valve) stenoses helps guide evaluation and management.

Diagnosis typically relies on imaging modalities such as echocardiography, cardiac magnetic resonance imaging, or computed tomography, which define the site and severity of obstruction and quantify pressure gradients. Clinically, patients may present with symptoms related to reduced pulmonary blood flow or signs of right ventricular hypertrophy; exam findings can include a systolic murmur.

Management ranges from observation for mild cases to interventional or surgical relief of obstruction for significant gradients. In tetralogy of Fallot, addressing the subpulmonic obstruction is a key component of definitive repair.