No abstract

A sample of 7,520 pregnancies, representative of the national population of Argentina was used to construct intrauterine Growth Charts. These are applicable nationwide and since 1974, when first designed, have proved efficient and more reliable in evaluating Argentine neonates than the Colorado Growth Charts. We have now evaluated the usefulness and have shown that despite certain changes, the Charts remain accurate and valuable as they were when first elaborated. Argentine infants do not grow at the same rate as those in other countries and, as expected, social and geographic variations can influence fetal growth. This effort should encourage the undertaking of similar ones in other Latin American countries, as they represent unique populations in need of knowledge of their own growth patterns.

The purpose of this investigation was to determine the influence of ionotropic agents upon systolic thickening and diastolic thinning of the left ventricular posterior wall. Two populations were investigated: #l--14 children with congenital cardiac disease who had echoes recorded at catheterization before and during isoproterenol infusion, and III--8 boys with Duchenne's muscular dystrophy who participated in a double-blind, placebo controlled, cross-over study of the effects of digoxin. All echoes were analyzed by digitizing left ventricular posterior wall endo-and epicardium and evaluating % systolic time and % diastolic time at standardized time intervals. No significant differences occurred when control and ionotropic group values were compared for either group at any percentage of systolic or diastolic time. Thus, the sequence of contraction and relaxation was unaltered by ionotropic agents. However, when wall thickness values at standardized time intervals were compared before and during administration of ionotropic agents, significantly greater (p<.01) systolic wall thickening was present at each time interval. A 15% mean additional systolic thickness occurred for isoproterenol and 10% mean increase occurred for digoxin. This investigation shows that ionotropic agents do not alter the shape of the systolic time or diastolic time curves but significantly change systolic contraction magnitude. Cardiac pathology in Duchenne's muscular dystrophy (DMD) is principally left ventricular posterior wall (LVPW) fibrosis. The aim of this study was to track long term LVPW echocardiographic (echo) changes in DMD. Echoes were recorded each 12 months from 19 boys with known DMD over 3 years and compared to controls. LVPW endo-and epicardium were digitized and % thickening and % thinning at standardized time intervals were determined; 15/19 had two-dimensional echoes. As previously reported, impaired diastolic relaxation was an early finding. The ratio of peak systolic LVPW to end diastolic LVPW was 2.06 (controls) to 1.83 (boys with DMD) (p<.01), but a given boy's ratio was not predictive. All 19 had LVPW thickness, adjusted for body size, below the control mean (p<.01). The major finding was that two wall pattern groups emerged: Group I-LVPW thickness increased normally with time and body surface area but at a low percentile curve. Group 11-LVPW decreased progressively and in 4, almost no systolic LVPW thickening was found. Two-dimensional echoes were studied for change in cavity size during contraction. All Group I patients had normal two-dimensional echoes. All Group I1 patients had abnormally decreased LV free wall contraction. Sequential abnormal findings in DMD patients are impaired LVPW relaxation, decreased LVPW thickness in systole and end diastole, and a contraction impairment imaged with two-dimensional echo. LONG TERM LEFT VENTRICULAR POSTERIOR WALL ECHOCARDIO- 146 EFFECTIVE TREATMENT OF NEONATAL SUPRAVENTRICULAR147 TACHYCARDIA WITH AMIODARONE Eduardo Halac, Cesar A.Vigo, Marcelo E. Arias and Jacobo Halac (Sp...