Morphology/Structure
The pulmonary fibrous ring consists of dense connective tissue which surrounds the orifice of the pulmonary trunk. The term “anulus” is a problematic description as the valvular anuli are not annular in shape and are often discontinuous. These annular rings are components of the fibrous skeleton of the heart. The location of the fibrous rings is often described as the origin of the sinuses where the semilunar hinges of the valve leaflets attach.
Key Features/Anatomical Relations
The pulmonary ring provides the attachment point for the three semilunar valve leaflets that sit at the junction between the ventricle and the pulmonary trunk.
Function
The pulmonary fibrous provides structural support and thus competency to the right atrioventricular valve and prevents over distension of the valve. It also provides a direct attachment for cardiac muscle. The collagen of the fibrous ring helps to separate electrical activities between the chambers by insulating the propagation of electrical impulses during a heartbeat.
List of Clinical Correlates
- Pulmonary regurgitation
