Localization of Regurgitant Common Atrioventricular Valve Commissures in Atrioventricular Septal Defects Using Color Flow Doppler Echocardiography

Abstract

The commissures of the five-leaflet common atrioventricular (A V) valve characteristic of the atrioventricular septal defect (AVSD) can be seen en face using a subcostal 2-dimensional echocardiographic imaging plane. If color flow Doppler is superimposed on this view, regurgitant AV valve flow can be localized to the specific incompetent commissure. To determine the accuracy of this technique, all children (n=8) undergoing surgical repair of an AVSD from January 1, 1992 to March 25, 1992 were prospectively studied using 2- dimensional and color Doppler echo cardiography. The comparisons were made with surgical observation of the regurgitant commissure determined after injection of saline. The patients ranged in age from 3 months to 39 years, weight from 5.7 kg to 55.0 kg, BSA from 0.26 m2 to 1.45 m2. Three patients had a single orifice valve and five had a 2-orifice common AV valve. Ventricular hypoplasia did not occur in any of the patients. The regurgitant commissures were determined using a subcostal imaging plane where the plane of sound was rotated to see the AV valve en face. Color flow Doppler was superimposed on this view and commissures where regurgitant flow occurred were located. Five patients had regurgitant flow preoperatively at the commissure between the antero-superior and anterior bridging leaflets, 5 between the left mural and the posterior bridging leaflets, 0 between the posterior bridging and the right mural leaflets, 0 between the right mural and the antero-superior leaflets, and 4 between the anterior bridging and posterior bridging leaflets. With the echo cardiographic techniques, 11 of 15 commissures with regurgitant flow were correctly identified. The echocardiographic techniques allowed correct identification of regurgitant flow with a 100% sensitivity and 89% specificity. The positive predictive valve of this technique was 73%. There was no correlation between orifice number, ventricular hypoplasia, or commissural location and the determination of the location of regurgitant flow. Thus, in patients with an AVSD, the regurgitant commissure can be located by adding color flow Doppler to the subcostal en face 2-dimensional imaging plane.