Serial echocardiographic measurements of the pulmonary autograft in the aortic valve position after the Ross operation in a pediatric population using normal pulmonary artery dimensions as the reference standard

Serial echocardiographic measurements of the annulus and sinus were obtaine d in children before the Pass operation, and early and late postoperatively . Values were compared with normal standards for the aorta and pulmonary ar tery (PA). There was no significant difference between PA annulus measureme nts before surgery and the corresponding autograft immediately afterward (1 .73 +/- 0.60 cm preoperatively; 1.63 +/- 0.58 cm postoperatively, p = NS). Late after surgery the mean annulus diameter was enlarged compared with the normal aorta (Delta Z 1.9 +/- 2.4), but remained relatively unchanged comp ared with the normal PA (Delta Z 0.7 +/- 1.1, p <0.01). In contrast, the ou tograft sinus was dilated early after surgery (1.83 +/- 0.58 cm preoperativ ely; 2.18 +/- 0.73 cm postoperatively, p <0.01). Mean sinus Z score further increased compared with both the aorta (Delta Z 1.3 +/- 1.7) and PA (Delta Z.1.3 +/- 1.6). Use of standard PA measurements may be important in the as sessment of autograft enlargement. Minimal change in autograft Z scores ove r time suggests that annulus enlargement is mainly due to somatic growth. I n contrast, the autograft sinus showed an immediate and continued dispropor tionate increase in size over time, suggesting that sinus enlargement is la rgely due to passive dilation. (C) 2000 by Excerpta Medica, Inc.