Usefulness of Insulinlike Growth Factor 1 as a Marker of Heart Failure in Children and Young Adults After the Fontan Palliation Procedure

• Published in: The American journal of cardiology 2015-03, Vol.115 (6), p.816-820
• Main Authors: Avitabile, Catherine M., MD, Leonard, Mary B., MD, MSCE, Brodsky, Jill L., MD, Whitehead, Kevin K., MD, PhD, Ravishankar, Chitra, MD, Cohen, Meryl S., MD, Gaynor, J. William, MD, Rychik, Jack, MD, Goldberg, David J., MD
• Format: Article
• Language: English
• Subjects: Age; Anatomy & physiology; Cardiovascular; Cardiovascular disease; Grants; Growth hormones; Heart failure; Insulin-like growth factors; Laboratories; Medical records; Morphology; NMR; Nuclear magnetic resonance; Standard deviation; Variables
• ISSN: 0002-9149; 1879-1913
• DOI: 10.1016/j.amjcard.2014.12.041

Growth hormone and its mediator, insulinlike growth factor 1 (IGF-1), are key determinants of growth in children and young adults. As patients with Fontan physiology often experience diminished longitudinal growth, we sought to describe IGF-1 levels in this population and to identify factors associated with IGF-1 deficiency. Forty-one Fontan subjects ≥5 years were evaluated in this cross-sectional study. Age- and gender-specific height Z scores were generated using national data. Laboratory testing included IGF-1 and brain natriuretic peptide (BNP) levels. IGF-1 levels were converted to age-, gender-, and Tanner stage–specific Z scores. BNP levels were log transformed to achieve a normal distribution (log-BNP). Medical records were reviewed for pertinent clinical variables. Predictors of IGF-1 Z score were assessed through the Student t test and Pearson's correlation. Median age was 11.1 years (range 5.1 to 33.5 years), and time from Fontan was 8.2 years (1.1 to 26.7). Mean height Z score was −0.2 ± 0.9 with a mean IGF-1 Z score of −0.1 ± 1.3. There was no association between IGF-1 Z score and height Z score. Longer interval since Fontan ( R  = −0.32, p = 0.04), higher log-BNP ( R  = −0.40; p = 0.01), and lower indexed systemic flow on cardiac magnetic resonance ( R  = 0.55, p = 0.02) were associated with lower IGF-1 Z scores. In conclusion, in this cohort with Fontan physiology, higher BNP and lower systemic flow were associated with lower IGF-1 Z score. Longitudinal studies are needed to determine if these relations represent a mechanistic explanation for diminished growth in children with this physiology and with other forms of congenital heart disease.