Three-dimensional quantitative echocardiographic assessment of ventricular volume in healthy human fetuses and in fetuses with congenital heart disease.

The purpose of this study was to evaluate the feasibility of three-dimensional freehand echocardiographic assessment of ventricular volumetry in healthy fetuses and in fetuses with congenital heart disease. The study was approved by the hospital institutional review board. After echocardiographic examination by conventional ultrasonographic equipment interfaced with a magnetic tracking system, three-dimensional cardiac data were collected prospectively in 57 fetuses. Ventricular volumes were determined from three-dimensional data sets, and 22 fetuses with congenital heart disease were compared with 29 healthy fetuses. A multiple regression analysis of covariance was performed to assess between-group differences. Gated three-dimensional volume data sets enabled assessment of ventricular volumes in 51 of the 57 fetuses. Both fetuses with and without congenital heart disease had exponential increases in cardiac volumes during gestation. In fetuses with congenital heart disease and a marked inequality of ventricular size but no heart failure, the combined end-diastolic and stroke volumes of both ventricles were found to be significantly reduced compared with controls with no disease and fetuses with other types of congenital heart disease. Three-dimensional imaging can provide estimates of ventricular volume changes in fetal hearts with abnormal ventricular morphology that cannot easily be performed by two-dimensional echocardiography, and it may provide insight into evolving congenital heart disease.

Echocardiographic assessment of aortic root dimensions in normal children based on measurement of a new ratio of aortic size independent of growth.

Two-dimensional echocardiography is commonly used as a method of monitoring aortic root dimensions in children with connective tissue disease. Measurements are usually standardized to body surface area (BSA) to account for growth. However, there are several theoretical and practical disadvantages to adopting this approach, and there has been little investigation of alternative methods of standardization. This study of 48 normal children and adolescents (age range 2 weeks to 23 years) was performed to determine the relation of 2-dimensional echocardiographic aortic root dimensions to indexes of body size and growth, and to examine a simple means of internally standardizing aortic root measurements to create an index of aortic root size independent of growth. Maximal diameters in the parasternal long-axis view were recorded at 4 levels: annulus, sinuses of Valsalva (SOV), supraaortic ridge (SAR), and ascending aorta (AAO). Ratios of aortic root size were created by internally standardizing aortic root diameters to aortic annular size. All diameters correlated closely with age, height, weight, and BSA (all r > 0.87). Linear regression in each case showed a significant positive slope (all p < 0.0001). The best predictor of aortic dimensions was height, with r values of 0.93 for annulus, SOV, and AAO, and 0.95 for SAR. Ratios of SOV/annulus, SAR/annulus, and AAO/annulus remained constant, with no correlation with age or any growth parameters. Mean values and 95% confidence limits were: SOV/annulus 1.37 (1.18-1.56); SAR/annulus 1.11 (0.95-1.28); and AAO/annulus 1.16 (0.97-1.35). Standardization to height, or the use of internally standardized aortic root ratios, provides a simple and accurate alternative to standardization to BSA for assessing aortic root dimensions in normal growing children.

Echo Doppler assessment of cardiac output and its relation to growth in normal infants.

In a study of 38 normal infants, serial measurements of systemic (n = 169) and pulmonary (n = 143) blood flow were undertaken from the ages of 2 weeks to 12 months by 2-dimensional, M-mode and pulsed Doppler echocardiography. Cardiac output changed linearly (cardiac output = 0.3 X height -0.99 liter/min), and cardiac index was validated as a means for standardizing cardiac output in infants younger than 10 to 13 months of age. Infants younger than 2 months had lower cardiac indexes and stroke volume indexes (2.6 +/- 0.7 liters/min/m2 and 19 +/- 5 ml/m2, respectively) compared with those aged 12 months (3.2 +/- 0.7 liter/min/m2 and 25 +/- 5 ml/m2, respectively). Changes in cardiac output in individual infants over time suggest nonmorphometric modulating factors for cardiovascular function.

Primary left ventricular rhabdomyosarcoma in a child: noninvasive assessment and successful resection of a rare tumor.

Rhabdomyosarcoma of the heart is a rare tumor, especially in childhood and particularly in the left ventricle. A primary tumor of this type was successfully resected after echocardiographic assessment alone in a young girl exposed prenatally to diphenylhydantoin. The patient is well and free of recurrence 2 1/2 years later.