Organ
Right atrium
Receives systemic veins before the right ventricle
High-yield
Use the crista terminalis, fossa ovalis and caval openings to orient the interior. The sinoatrial node lies near the superior caval junction rather than inside the chamber cavity.
Overview
The venae cavae and coronary sinus empty into this chamber on the right side of the heart. The crista terminalis marks the change from its smoother venous region to the muscular ridges of the anterior wall and appendage.
Reference facts
- Location
- Rightward cardiac chamber receiving systemic venous blood and opening through the tricuspid valve
- Parts
- Smooth venous portion, pectinate-muscle region, right appendage and septal surface with the fossa ovalis
- Blood supply
- Primarily atrial branches of the right coronary artery; nodal supply can vary
- Innervation
- Sympathetic and vagal fibers through cardiac plexuses influence atrial and nodal tissue
- Relations
- Superior and inferior caval openings; coronary sinus opening near the inferior septal/tricuspid region
- Venous/Lymphatic drainage
- Smallest cardiac veins may empty directly into the atrial cavity
- Function
- Collects venous return and passes it to the right ventricle during filling
Clinical correlation
The crista terminalis is a recognized source of focal atrial tachycardia. Its normal muscular contour is also important when interpreting right atrial imaging.
Frequently asked questions
Where is the right atrium located?
The right atrium lies rightward cardiac chamber receiving systemic venous blood and opening through the tricuspid valve.
What does the right atrium do?
Collects venous return and passes it to the right ventricle during filling.
What are the parts of the right atrium?
The parts of the right atrium are the smooth venous portion, pectinate-muscle region, right appendage and septal surface with the fossa ovalis.
What is the blood supply of the right atrium?
Primarily atrial branches of the right coronary artery; nodal supply can vary.