The crux cordis (Latin for "cross of the heart" or "crucial point of the heart") is a significant anatomical landmark located on the posterior-inferior surface of the human heart. It is the point of intersection where several major anatomical structures converge, typically forming a cross-shaped configuration.
Etymology
The term "crux" (Latin for "cross" or "difficult point") refers to the cross-like meeting point of sulci (grooves) and septa (walls). "Cordis" is the genitive singular of cor, meaning "of the heart."Anatomy
The crux cordis is precisely defined as the junction where the following three structures primarily meet on the external surface of the heart:- The coronary sulcus (or atrioventricular groove), which encircles the heart and separates the atria from the ventricles.
- The posterior interventricular sulcus (or posterior descending groove), which runs inferiorly on the posterior surface, marking the boundary between the right and left ventricles.
Internally, this region corresponds to the meeting point of the interatrial septum and the interventricular septum, often forming a critical point in the overall septal architecture of the heart. This convergence typically occurs at the superior aspect of the diaphragmatic surface of the heart.
Clinical Significance
The region of the crux cordis is clinically important for several reasons:- Coronary Artery Distribution: The posterior interventricular artery (PVA), which supplies the posterior wall of both ventricles and the posterior third of the interventricular septum, typically descends within the posterior interventricular sulcus, originating near the crux. The dominance of the coronary circulation (right-dominant, left-dominant, or co-dominant) is determined by which major coronary artery (right coronary artery or circumflex artery, a branch of the left coronary artery) gives rise to the PVA at or near the crux.
- Surgical Landmark: It serves as a surgical landmark during cardiac procedures, particularly in understanding the septal architecture, coronary vessel anatomy, and during interventions involving the posterior aspect of the heart.
- Anatomical Variation: While its presence is consistent, the exact morphology of the sulci and the arterial supply in this region can exhibit individual variations.
See Also
- Heart
- Coronary circulation
- Cardiac anatomy
- Coronary sulcus
References
- Standring, S. (Ed.). (2016). Gray's Anatomy: The Anatomical Basis of Clinical Practice (41st ed.). Elsevier.
- Netter, F. H. (2014). Atlas of Human Anatomy (6th ed.). Saunders.
- Moore, K. L., Dalley, A. F., & Agur, A. M. R. (2018). Clinically Oriented Anatomy (8th ed.). Wolters Kluwer.