The risk of having additional obstructive lesions in neonatal coarctation of the aorta

Infants with coarctation Of the aorta may have obstructions at other sites within the left heart which are not always apparent on the initial echocard iogram. The magnitude of the risk of having the additional obstructions is not well described, with few reliable quantitative criterions for identifyi ng patients at the highest risk. We determined the frequency of additional, late appearing, stenotic lesions within the left heart, and the predictive morphologic features on the initial cross-sectional echocardiogram. We identified all patients with coarctation of the aorta diagnosed by 3 mon ths of age, excluding those with complex cardiac disease or definite additi onal stenotic lesions at presentation, leaving 101 patients for study. At f ollow-up, 31 stenotic lesions were diagnosed in 23 patients, 15 of whom had at least 1 intervention. Mitral stenosis was diagnosed in 11 patients, aor tic stenosis in 10, subaortic stenosis in 8, and supravalvar aortic stenosi s in 2. The probability for freedom from obstructive lesions was 81% at 1 y ear, 74%; at 3 years, and 70% at 5 years. Echocardiographic predictors of m itral stenosis included smaller mitral valvar annuluses, presence of a mean transmitral gradient between 2.5 and 5.0 mmHg, and elongation of the area of intervalvar fibrous continuity. Predictors of aortic stenosis were small er mitral valvar annuluses, an initial aortic valvar gradient between 15 an d 20 mmHg, and obliteration of the commissure between the right and non-cor onary leaflets of the aortic valve. Predictors of subaortic stenosis were s maller mitral valvar annuluses and elongation of the area of intervalvar fi brous continuity. Patients with Z-scores for the diameter of the mitral val ve of less than -1 were at the highest risk for manifesting obstructive les ions at any level. Associated stenoses in the left heart are common in the setting of aortic c oarctation. When Doppler data is equivocal, features of the cross-sectional echocardiogram can identify the sub-group of infants at increased risk.