The fractional shortening-velocity ratio: validation of a new echocardiographic Doppler method for identifying patients with significant aortic stenosis.

Previous studies have shown that Doppler echocardiographic methods based on the continuity equation can accurately determine aortic valve area in patients with clinically significant aortic stenosis; nonetheless, methods based on the continuity equation are time-consuming and may not be technically possible in all subsets of patients. The purpose of this study was to develop and prospectively evaluate a simpler new noninvasive method for determining aortic valve area. With this new method, aortic valve area is obtained by dividing the percent fractional anteroposterior shortening at the midventricular level by 4V2, where V is the peak instantaneous Doppler-derived flow velocity across the aortic valve. In the first part of the study, the fractional shortening-velocity ratio was used to examine a group of 25 patients evaluated retrospectively. There was a highly significant linear relation between the fractional shortening-velocity ratio (FSVR) and the aortic valve area (AVA) determined by the Gorlin formula at cardiac catheterization: FSVR = 1.1(AVA) - 0.1 (r = 0.88; significance of slope p less than 0.001). Furthermore, a fractional shortening-velocity ratio less than 1.1 reliably identified all patients with clinically significant aortic stenosis (aortic valve area less than 1 cm2), whereas a fractional shortening-velocity ratio less than 0.8 reliably identified all patients with critical aortic stenosis (aortic valve area less than 0.7 cm2). This new method was then validated by prospectively applying the fractional shortening-velocity ratio to a group of 44 patients from two separate institutions.(ABSTRACT TRUNCATED AT 250 WORDS)