POSSIBILITY OF POSTNATAL LEFT-VENTRICULAR GROWTH IN SELECTED INFANTS WITH NON-APEX-FORMING LEFT-VENTRICLES

To evaluate postnatal left ventricular growth potential, we reviewed t he echocardiograms of seven infants with left ventricles that did not form an apex. Prostaglandins were used to maintain patency of the duct us arteriosus in six infants. Associated abnormalities included aortic stenosis in five, coarctation in three, and left atrial isomerism in one. Initial echocardiographic measurements (7 +/- 9 days) were compar ed with measurements at 1 month (36 +/- 9 days). Weight (3.0 +/- 0.1 v s 3.0 +/- 0.5 kg) and body surface area (BSA) (0.2 +/- 0.01 vs 0.2 +/- 0.01 m(2)) did not change. Comparing initial measurements with measur ements at 1 month, there were significant increases (p < 0.05) in aort ic annulus diameter (4.5 +/- 0.5 vs 5.6 +/- 0.7 mm), aortic root diame ter indexed to BSA (2.9 +/- 0.5 vs 3.7 +/- 0.7 cm/m(2)), ratio of the long axis of the left ventricle to the long axis of the heart (0.74 +/ - 0.1 vs 0.86 +/- 0.1), left ventricular end-diastolic volume indexed to BSA (10 +/- 2 vs 24 +/- 9 ml/m(2)), left ventricular mass indexed t o BSA (27 +/- 13 vs 47 +/- 28 gm/m(2)), mitral valve area indexed to B SA (2.3 +/- 0.5 vs 3.2 +/- 0.7 cm(2)/m(2)), left ventricular area (2.1 +/- 0.5 vs 3.6 +/- 1.1 cm(2)), and Rhodes score (-2.7 +/- 0.5 vs -1.1 +/- 0.9). Tricuspid valve area indexed to BSA (5.8 +/- 1.5 vs 6.1 +/- 1.1 cm(2)/m(2)) and long axis of the heart indexed to BSA (13.0 +/- 2 .8 vs 13.6 +/- 2.9 cm/m(2)) did not change. The increase in measuremen ts appeared adequate for biventricular physiology in five infants (fou r are alive [3.9 +/- 2.6 years] and one died after not being able to w ean from the ventilator). These data suggest that a non-apex-forming l eft ventricle may have postnatal growth potential.