1. Echocardiography of hypoplastic ventricles
Norman H Silverman, MD, Doff B McElhinney, MD 
The Annals of Thoracic Surgery 
Volume 66, Issue 2, Pages (August 1998)
DOI: /S (98)

2. Fig 1
Different geometric models used to calculate chamber volumes from two-dimensional echocardiography. (I) The biplane Simpson’s rule based on orthogonal views in an apical two- and four-chamber view. The volume is calculated as the sum of volumes of ellipsoidal cylinders with the major and minor axis a and b and the height L/n, where L is the common long axis and n the number of segments chosen. In the example shown n equals 20. (II, III) The principle of Simpson’s rule can be applied to a different method that calculates the chamber volume from three (II) or four (III) area measurements obtained in the parasternal short axis; the height of the segments is taken from equivalents of the long axis measured from the apical window. The assumption that all slices in the parasternal short axis are equidistant from each other and are perpendicular to the long axis is almost impossible to satisfy in practice. (IV) Using a biplane area-length method, the areas A1 and A2 are traced in apical two- and four-chamber views; the long axis L is taken from either plane. The formula used in this calculation is that for an ellipse, which may be reasonable for the left ventricle, but not for the right ventricle. (V) The hemisphere-cylinder (or bullet) model uses a cross-sectional area of the left ventricle in a parasternal short axis at the level of the tips of the papillary muscles and a length taken from an apical view. The formula considers the chamber volume as the sum of a hemisphere and a cylinder, which is also not valid for the right ventricle. (VI) Biplane ellipsoidal method using the length L taken from an apical plane and the diameters D1 (anteroposterior) and D2 (lateral) taken from a parasternal short axis at the level of the tips of the papillary muscles. This model can also be used only for left ventricular volume calculation. (VII) The single area-length method is similar to the biplane area-length method (IV), but assumes both orthogonal areas to be equal; either the apical two- or four-chamber view may be used with this method. (Reproduced with permission from Silverman NH, Snider AR. Two-dimensional echocardiography in congenital heart disease. Norwalk: Appleton-Century-Crofts, 1982.)
The Annals of Thoracic Surgery  , DOI: ( /S (98) )

3. Fig 2
Subcostal coronal (top) and sagittal images (bottom) in diastole (left) and systole (right) indicating the area outlines for the right ventricle (RV) using the Simpson’s rule method. The common long axis for the right ventricle is shared by the pulmonary valve superiorly and the diaphragmatic surface of the left ventricle (LV) inferiorly. The area outlines indicate the changes in the normal right ventricle in systole and diastole (AO = aorta; PA = pulmonary artery; RA = right atrium.)
The Annals of Thoracic Surgery  , DOI: ( /S (98) )

4. Fig 3
(A) (Top) End-systolic frame of the right (left) and left (right) ventricles (top) in a patient with pulmonary atresia. (Bottom) Superimposition of Doppler color-flow maps with the Nyquist limit lowered to identify the blood flow pool more accurately, after which the area outlines of the right (left) and left ventricle (right) can be traced. The right ventricular area is substantially larger than if color flow information had not been added. (B) An example of pulmonary atresia with intact septum and hypoplastic right ventricle. (Left) The arrows in the right atrium (RA) indicate the tricuspid annulus size. (Right) A two-dimensional tissue-tagged image facilitates characterization of right ventricular size, which has been traced manually. (LA = left atrium; LV = left ventricle; RV = right ventricle.) (Figures reproduced in black and white.)
The Annals of Thoracic Surgery  , DOI: ( /S (98) )

5. Fig 4
(Top) Apical four-chamber view in a patient with pulmonary atresia and intact septum. The right (RA) and left (LA) atria and right (RV) and left (LV) ventricles are shown. The area ratio between the right and left ventricles is (Bottom) Area outlines drawn over these particular images from which the ratios were established.
The Annals of Thoracic Surgery  , DOI: ( /S (98) )

6. Fig 5
Diagram of the technique used to calculate left ventricular (LV) mass. The top three diagrams show the area outline of the left ventricular outer wall echoes and the corresponding area A1, at papillary muscle tip level. A2 is the endocardial area at the level of the tips of the papillary muscles at end-diastole. The papillary muscles are excluded from this area outline. The thickness (t) at this level is calculated by subtracting the two areas Am = A1 − A2. To calculate the cord (b) from the area and the mean thickness (t), the manipulations in the formula are shown. The bottom diagram shows the various cords used in the formula to calculate mass from the truncated ellipse (TE). The dimensions b and t have been defined. The long axis from the widest minor axis radius to the apex is the dimension (a), and (d) is the truncated semimajor axis from widest short-axis diameter to mitral annulus plane as shown. The bottom formula for left ventricular mass is the truncated ellipse and is in current use on our computer system. The top formula is used for the area length (AL) method. (Reproduced with permission from Schiller NB, Shah PM, Crawford M, et al. Recommendations for quantitation of the left ventricle by two-dimensional echocardiography. J Am Soc Echocardiogr 1989;2:358–67.)
The Annals of Thoracic Surgery  , DOI: ( /S (98) )

7. Fig 6
(A) Parasternal long-axis view in a patient with a variant of the hypoplastic left heart syndrome, which shows some forward flow across the stenotic left ventricular outflow tract, into a diminutive aorta (AO) and left ventricle (LV). The right ventricle (RV) is apex-forming and has a very heavily trabeculated moderator band apparently dividing the right ventricle into two sections. (B) Doppler color-flow image taken in a similar position in systole demonstrates a jet from aortic stenosis (AS), indicating some forward flow across the aortic valve and mitral regurgitation (MR). (C) Apical four-chamber view, again demonstrating the diminutive left ventricle, the large coronary sinus (CS), the hypoplastic left atrium (LA), the large right atrium (RA), and the right ventricle (RV).
The Annals of Thoracic Surgery  , DOI: ( /S (98) )