Location of the heart.
The human heart sits snuggly behind the sternum and slightly left-sided in the chest cavity.
It is protected by the sternum (anteriorly), ribcage and lungs (laterally) and the spine (posteriorly).
Main components of the heart.
- Atria: Smaller and more superior chambers.
- Ventricles: Larger and most inferior chambers of the heart.
- Major arteries transports blood away from the heart.
- Major veins transports blood towards the heart.
- Pulmonary vessels connect with the hilum of the lungs.
- The aorta transport the systemic blood while
- the venae cavae (major veins) return the systemic deoxygenated blood to the heart.
Mediastinum
The thoracic cavity is devided into a superior compartment (superior mediastinum) and an inferior compartment (inferior mediastinum).
The inferior mediastinum (the larger of the 2 compartments) is further divided into the anterior, middle and posterior mediastinum.
The heart is located in the middle inferior mediastinum (MIM) that stretches between the left and right pleural sacs of the lungs.
The MIM is demarcated by:
- Plane of Ludwig (superiorly)
- the pleura of the lungs (laterally),
- the sternum (anteriorly)
- vertebral column (posteriorly)
- and diaphragm (inferiorly)
The Plane of Ludwig that demarcates the superior border of the mediastinum is a horizontal plane connecting the sternal angle and the T4/T5 vertebra junction.
View these structures in the application by opening the ribs and hovering over the structures.
