Estimation of the Severity of Aortic Incompetence From Prolongation of the Left Ventricular Ejection Time

The regurgitant fraction of the total left ventricular stroke index was estimated by a new method in 30 patients with pure aortic incompetence and compared with cineaortographic findings. The total stroke index was derived from the left ventricular ejection time, heart rate, and aortic diastolic pressure. The assumption was made that the interrelationships between the four variables in aortic incompetence are not different from those, found by others, in normal subjects at rest and during exercise. The forward stroke index was determined by Fick's method. The regurgitant fractions varied between 0 and 75% and showed a close correlation to the angiographic severity of aortic incompetence. The correlation exceeded that offered by prolongation of the ejection time alone, aortic diastolic pressure alone, or aortic pulse pressure. The method seems suitable for estimation of aortic incompetence in the absence of significant aortic valve obstruction and even in the case of failing left ventricle. It is simple to apply, as all the variables are easily determined at routine cardiac catheterization without using any additional equipment.