[A bloodless evaluation of the gradient of valvular and subvalvular aortic stenosis. Correlations with the hemodynamic picture. (author's transl)].

53 patients affected by congenital valvular or discrete aortic stenosis have been evaluated in order to compare the observed gradient with the one expected according to multifactorial analysis based on electrocardiographic and auscultatory data deviced by Ellison et al. There Authors employed this formula for the evaluation of the valvular form only. In our experience all cases of valvular stenosis showing an estimated gradient less than or equal to 40 mmHg were found to have a gradient less than or equal to 40 mmHg at the catheterization. This statement is true in the discrete form as well, only if the estimated gradient was less than or equal to 30 mmHg. The regression curve between the two gradients shows a r = 0.718 (p less than 0.01); an even better correlation was found in the valvular forms (r = 0.816; p less than 0.01). These results are very useful since they allow to restrict indication to catheterization only to the cases in which the obstruction is estimated to necessitate a surgical intervention.