Table 8.

Advantages and Limitations of Echocardiographic Techniques Used for Ventricular Functional Assessment

Method	Assessment Type	Geometrical Assumption	Advantages	Limitations
Linear	M-mode	Yes	Quick and easy to perform	Assumes an ellipsoid shaped ventricle Needs perpendicular parasternal imaging Depends on acoustic window Therefore, least accurate method
2D	Simpson's biplane	Yes	More accurate and reproducible than M-mode.	Assumes an ellipsoid shaped ventricle Needs unforeshortened orthogonal views Depends on acoustic window and operator experience Endocardium often not fully visualized in a single frame used for manual tracing
2D contrast	Simpson's biplane	Yes	More accurate and reproducible than 2D Less susceptible to poor image quality	As 2D; but less susceptible to poor image quality
3D biplane	Simpson's biplane	Yes	2 orthogonal planes from the same beat Avoids off-axis views and foreshortening	Assumes an ellipsoid shaped ventricle Depends on acoustic window and operator experience Full volume recordings require stable heart rhythm and breath hold (usually 4 beats) otherwise stitching artifacts Real time acquisition reduces image quality Lower spatial and temporal resolution than 2D
3D	Voxel count	Partial	Avoids off-axis views and foreshortening Automatic border delineation following minimal landmark allocations More accurate than 2D and 3D biplane	Depends on acoustic window and operator experience Full volume recordings require stable heart rhythm and breath hold (usually 4 beats) otherwise stitching artifacts Real time acquisition reduces image quality Lower spatial and temporal resolution than 2D Has problems fitting to some abnormal LV shapes (i.e. apical infarcts)
3D contrast	Voxel count	Partial	Best agreement with CMR and CT angiography	Few studies available Artifacts from apical contrast destruction and attenuation Lowest spatial and temporal resolution Not all software packages can perform LV assessment with the addition of contrast

LV = left ventricle; 2D = two-dimensional; 3D = three-dimensional; CMR = cardiac magnetic resonance imaging; CT = computed tomography.