Pulmonary Valve in Heart Transverse Section

Description

Positioned at the junction of the right ventricular outflow tract and the pulmonary trunk, the pulmonary (pulmonic) valve appears as three semilunar cusps arranged around a central orifice in a transverse section of the heart. Each cusp attaches peripherally to the fibrous annulus at the level of the ventriculoarterial junction, while the free margins project toward the arterial lumen to form coaptation lines. Superior to the valve lies the proximal pulmonary trunk, and inferior to it the muscular infundibulum (conus arteriosus) of the right ventricle. Commissures sit at the cusp junctions, defining the tri-radiate geometry characteristic of the normal valve. Seeing the pulmonary valve en face in transverse section helps clarify how a semilunar valve actually seals, by cusp apposition under diastolic pressure rather than chordae tendineae and papillary muscle tethering. That distinction matters in congenital and interventional cardiology, where pulmonary valve stenosis (often with doming cusps and post-stenotic dilation of the pulmonary artery) and repaired right ventricular outflow tract lesions are assessed for residual obstruction or regurgitation. It is also the anatomic basis for transcatheter pulmonary valve implantation planning, where annular sizing and the relationship to the pulmonary trunk and infundibulum guide device choice. Small structure, large hemodynamic consequences. Use this artwork in cardiothoracic anatomy teaching to contrast semilunar versus atrioventricular valve architecture, or in congenital heart disease materials discussing RVOT obstruction, tetralogy of Fallot repair, and pulmonary regurgitation. It also supports journal figures and slide decks that need a clean transverse section reference for the pulmonary valve cusps and commissures. Anatomical accuracy verified by SciePro's Medical Advisory Board.