Significance of Aortic Root Motion in Echocardiographic Evaluation of Left Ventricular Function in Children with Dilated Cardiomyopathy

Thirty-one children with dilated cardiomyopathy (DCM), subdivided into two groups, were evaluated by 2-D and M-mode echocardiogrphy. Group I consisted of 20 patients with ongoing signs and symptoms and echographic evidence of DCM, whereas Group II consisted of 11 DCM patients who were "normalised" during the course of follow-up and treatment. Careful mearusements of the aortic root dimension and aortic wall motion were carried out. The "aortic root motion", the ratio of average aortic wall motion to aortic dimension at enddiastole, was introduced as a new parameter. Also, the "aortic root expansion ratio", was calculated as the ratio of cyclic difference of aortic dimension to the aortic dimension at end-diastole. Results were compared with those from twenty-four healthy children. The "aortic root motion" was found to be 56.2±7.13 % in healthy children. Group I had much depressed values (39.9±11.0 %). The "normalized patients" of Group II had values (44.6±7.17 %) that, although significantly higher than in the former group, were still significantly below those from normal children. This new prameter differentiated all three groups from one another (p<0.01 for all groups). The "aortic root expansion ratio" differentiated only Group I from the two other groups. The "aortic root motion" correlated well with left ventricular shortening fraction (r=0.69, p<0.001) when all the children were evaluated together in a large group (n=55), but showed no significant correlation within each group. We concluded that this new parameter of ventricular systolic function can be useful in the long-term serial follow-up of patients with dilated cardiomyopathy.