Septal Leaflet of the Tricuspid Valve Visualized Transversely

Description

Oriented in transverse section through the right heart, the septal leaflet of the tricuspid valve (valva tricuspidalis) is seen arising from the fibrous annulus and tethered medially toward the interventricular septum, forming part of the right atrioventricular orifice. The leaflet margin faces the right ventricular cavity and relates laterally to the anterior and posterior tricuspid leaflets, while chordae tendineae descend inferiorly to papillary muscle heads and the trabeculated right ventricular wall. Superior to the leaflet plane, the right atrium lies proximal to the valve ring; inferiorly, the right ventricle expands toward the apex. A transverse cut is the teaching sweet spot for appreciating how the septal leaflet differs from the mitral anterior leaflet: it inserts adjacent to the membranous septum and sits close to the atrioventricular conduction axis. That relationship matters in practice. Surgical tricuspid annuloplasty, valve repair for functional tricuspid regurgitation, and closure of perimembranous ventricular septal defects all place sutures near the septal leaflet hinge, where injury to the bundle of His can produce postoperative atrioventricular block. Use this artwork in cardiothoracic anatomy labs, pathology teaching on tricuspid regurgitation and endocarditis involving the septal leaflet, and surgical education materials outlining right atrioventricular valve repair in relation to the ventricular septum and conduction tissue. It also fits well in echocardiography and CT/MR correlation chapters that explain how transverse imaging planes intersect the tricuspid valve apparatus. Anatomical accuracy verified by SciePro's Medical Advisory Board.