The left ventricle is one of four heart chambers. It receives oxygenated blood from the left atrium and pumps it into the systemic circulation via the aorta.
The left ventricle is conical in shape with an anteroinferiorly projecting apex and is longer with thicker walls than the right ventricle. It is separated from the right ventricle by the interventricular septum, which is concave in shape (i.e. bulges into the right ventricle). Internally, there are smooth inflow and outflow tracts and the remainder of the left ventricle (mainly apical) is lined by fine trabeculae carneae. The ventricular wall is thickest at the base and thins to only 1-2 mm at the apex.
Blood flows in via the atrioventricular orifice lined by the mitral valve and flows out passing through the aortic valve into the aorta.
There are two papillary muscles that attach to the mitral valve via chordae tendineae:
- anterior lateral (anterolateral)
- posterior medial (posteromedial)
- arterial supply
- left anterior descending artery: supplies the free wall and most of the papillary muscles
- left circumflex artery: supplies the free wall
- venous drainage
- great cardiac vein, middle cardiac vein, and posterior vein of the left ventricle: drain into the coronary sinus
- tiny myocardial thebesian veins drain directly into the left ventricle
- anterior: interventricular septum, right ventricle
- posterior: descending aorta, left vagus nerve, sympathetic chain
- superior: left atrium
- right: right side of pleura
- left: left lung pleura and left phrenic nerve
- double-inlet ventricle: inflow from both the right and left atria
- parachute valve: mitral valve chordae tendineae inserting into a single papillary muscle
On contrast-enhanced chest CT and cardiac MRI, the left ventricle when measured on axial slices can be considered enlarged when the transverse diameter is ≥58 mm (male) and ≥53 mm (female) .