Apical 4 Chamber

Surface Anatomy

The transducer marker is directed at the right shoulder. This places the left ventricle on the left side of the image with the apex seen at the top. The interventricular septum and interatrial septum are seen separating the ventricles and atria respectively. Blood flow is parallel to the ultrasound beam, allowing accurate doppler measurements of flow velocity across the tricuspid, mitral and aortic valves.

3d

Normal 2d

apical 4 chamber

Four chambers are seen with ventricles at the top and atria at the bottom of the image.

Cavities

apical 4 chamber cavities

Note the relative size of the right and left ventricles. The right ventricle is the smaller cavity and is roughly two thirds the size of the left ventricle. The right ventricle does not extend to the left ventricular apex. In addition at the crux of the heart, the septal leaflet of the tricuspid valve is closer to the apex than the anterior leaflet of the mitral valve. A moderator band (within the apical third) and trabeculae are seen within the right ventricle. These features help to distinguish the morphological right from left ventricle. Quantification of relative ventricular sizes are done in this view, an important index when diagnosing right ventricular volume overload.

Walls

apical 4 chamber walls

The basal, mid and apical portion of both the inferoseptal and anterolateral left ventricular walls (6 of 17 segments) are visible. The apex should be visualised. Note the interventricular and interatrial septa in this view.

Valves

apical 4 chamber valves

The mitral valve leaflets and annulus are visible. Colour flow doppler imaging should be applied here to look for/ quantify mitral regurgitation. Two of the three tricuspid valve leaflets are visible.

2d Video