Mitral valve E point to ventricular septal separation in infants and children.

This investigation establishes heretofore unavailable norms that permit clinical application of mitral valve E point to ventricular septal separation (EPSS) as an ejection phase index in infants and children. The study consisted of 105 normal subjects (1 day through 15 years of age, mean 7.4 years) and 67 patients of comparable age. Fifty-seven patients had increased left ventricular (LV) volume with normal function (ventricular septal defect or patent ductus arteriosus) and 10 patients had increased LV volume with depressed function (dilated cardiomyopathy). In normal subjects, EPSS was 2.5 +/- 1.7 mm and "normalized" EPSS, that is, the ratio of EPSS to end-diastolic dimension (EPSS/EDD), was 0.08 +/- 0.06 (mean +/- standard deviation); there was no correlation between either of these indexes and age, body surface area, height or weight. In patients with ventricular septal defect or patent ductus arteriosus, or both, the EPSS and EPSS/EDD were similar to those of normal subjects (3.2 +/- 2.3 mm and 0.09 +/- 0.06 mm, respectively). In patients with dilated cardiomyopathy, these indexes were significantly increased (p greater than 0.05) (EPSS 16.5 +/- 5.1 mm; EPSS/EDD 0.39 +/- 0.09). The data provide normal values for EPSS and EPSS/EDD in infants and children and show that these indexes are independent of age, body surface area, height or weight. Mitral valve EPSS and EPSS/EDD can now be used in pediatric echocardiography as a simple, practical and accurate means of separating normal from abnormal LV function.