Pulmonary valve stenosis in the adult patient: pathophysiology, diagnosis and management

### Learning objectives The most common form of right ventricular outflow tract (RVOT) obstruction is pulmonary valve stenosis. Pulmonary stenosis (PS) occurs in isolation in 8%–10% of congenital heart disease but is often associated with other congenital lesions1 Subvalvar and supravalvar PS are less common but also seen in adults. PS and supravalvar PS are most often congenital and can be associated with genetic syndromes including Noonan, Alagille and Williams syndromes as well as congenital rubella. PS can also be an acquired condition such as rheumatic heart disease, carcinoid, infective endocarditis or result from trauma. Pulmonary valve disease is often accompanied by pulmonary regurgitation (PR) as a result of inherent abnormalities of the valve or from prior intervention. This review will focus primarily on isolated forms of pulmonary valve disease in adults. Abnormalities of the pulmonary valve, subvalvar or supravalvar region can lead to RVOT obstruction. The primary consequence of PS is pressure overload of the right ventricle, the degree of which is dependent on the severity of the stenosis. Pressure overload of the right ventricle results in increased contractility and dilation leading to increased wall stress and compensatory right ventricular hypertrophy. Increased muscle mass allows for the right ventricle to maintain a normal cardiac output. Right ventricular hypertrophy may cause a decrease in ventricular compliance and result in increased right ventricular end-diastolic pressures and increased right atrial pressures. Right-to-left shunting may occur if there is an interatrial communication. Over time, progressive right ventricular hypertrophy and stiffness can give rise to right ventricular diastolic and systolic dysfunction. Chronic severe PR results in right ventricular dilation. Increased right ventricular end-diastolic …