[Comparative study of left ventricular echocardiographic parameters in congenital aortic stenosis and coarctation].

Left ventricular adaptation to obstruction to ejection (aortic stenosis and coarctation) was studied by echocardiography in 85 patients from 1 month to 20 years of age. Group I: 40 children with pure congenital aortic stenosis. Group II: 45 children with coarctation at the aortic isthmus without associated shunts. All patients also underwent cardiac catheterisation. The results were compared with a control series of 35 normal subjects. Echocardiographic recordings of adequate quality for studying the left ventricle and parameters of myocardial performance were obtained in all patients. In Group I estimations of the left ventricular systolic pressure and the ventriculo-aortic pressure gradient were made and compared to the results of catheterisation. Symmetric left ventricular hypertrophy was recorded in both groups (h/R, p less than 0,001; myocardial mass, p less than 0,001) but this was more common in aortic stenosis (92%) than in coarctation (53%). Left ventricular function was similar in both groups with an increased fractional shortening (p less than 0,001) and velocity of circumferential fibre shortening (p less than 0,001). Good correlations were obtained between echocardiographic and hemodynamic measurements of left ventricular pressures and ventriculo-aortic pressure gradients (pressure R = 0,83, gradient R = 0,73) using the formula for systolic left ventricular pressure = SLV = 225 X PPs/Ds. This proved very useful in assessing which children needed surgery.