Aortic Valve Cusp Names
The normal tricuspid aortic valve has three cusps: the right coronary cusp, the left coronary cusp, and the non-coronary cusp. 1
Anatomical Position and Relationships
The three cusps have specific anatomical positions relative to surrounding cardiac structures:
Right coronary cusp (R): Located anteriorly, positioned between the tricuspid valve and pulmonary valve insertions 1
Left coronary cusp (L): Positioned posterior-laterally, related to the left atrium 1
Non-coronary cusp (N): The most posterior cusp, related to the interatrial septum 1
Clinical Significance of Nomenclature
The coronary arteries originate from the right and left cusps (hence their names), while no coronary artery arises from the non-coronary cusp 1. These anatomical relationships are critical for:
- Echocardiographic identification during imaging
- Surgical planning and valve repair procedures
- Determining fusion patterns in bicuspid aortic valve variants
- Understanding valve pathology and dysfunction
Morphological Variations
Research has shown that the non-coronary cusp is significantly larger than both the left and right coronary cusps (mean height 20.7 mm vs 20.0 mm for both coronary cusps, P = .000), while the left and right coronary cusps show no significant size difference between them 2. The non-coronary cusp also demonstrates smaller fiber bundle diameter (0.9 mm) compared to the coronary cusps (1.1 mm) 3.
These landmark anatomical relations of each cusp relative to adjacent cardiac structures are essential for proper valve identification in all imaging modalities including transthoracic echocardiography, cardiac CT, and cardiac MRI 1.