IGF-I replacement therapy in children with congenital IGF-I deficiency (Laron syndrome) maintains heart dimension and function

Objective: Untreated patients with congenital growth hormone deficiency (GHD) and IGF-I deficiency are characterized not only by dwarfism but also by acromicria and organomicria, such as the heart. We assessed cardiac dimensions and function in very young patients with Laron syndrome (LS) undergoing IGF-I replacement therapy. Design: Two to seven echocardiographic measurements were performed during IGF-I replacement therapy on male (n = 4) and female (n = 4) LS-atients, mean +/- SD age of 7.1 +/- 3.6 years (range 1.6-11.6 years), weight 16.1 +/- 9.7 kg, and height 89.9 +/- 18.5 cm. As aged- and gender-matched controls served 44 healthy children, age: 8.7 +/- 5.5 years, weight: 36.1 +/- 22.4 kg, and height: 129.7 +/- 33.1 cm. Data of LS patients were normalized to body surface area and compared to the control group as well as nomograms of normal echocardiographic parameters for this age group. Results: Left ventricular diastolic and systolic dimensions (LVDD/LVSD, mm) and LV mass (gr) were significantly smaller in boys and girls with IGF-I treated LS compared with controls while the shortening fraction (%) and intraventricular septum thickness (mm) were similar. When compared with standard values for this age group, all treated LS patients were within I standard deviation of the mean. Conclusion: IGF-I therapy of young patients with Laron syndrome maintain LV dimensions and function within the normal range of aged-matched controls. (C) 2008 Elsevier Ltd. All rights reserved.