Anomalies of the Right Ventricular Outflow Tract and Pulmonary Valve

Anomalies of the right ventricular (RV) outflow tract and pulmonary valve result in a variable combination of obstruction and regurgitation. The latter can occur either as the primary manifestation of disease, as is the case in absent pulmonary valve syndrome, or as a consequence of either surgical or catheterization management of obstructive lesions. This chapter focuses on isolated abnormalities of the RV outflow tract. RV outflow tract abnormalities associated with other complex conditions will be discussed in other parts of this book. Pathology of the RV outflow tract is divided into the following headings: malformations affecting the pulmonary valve, subpulmonary stenosis, absent pulmonary valve (nonconotruncal), and main pulmonary artery stenosis.