Abstract 9765: The Impact of Premature Lung Disease on the Maturation of Cardiac Function in the First Year of Life: Discerning Early Predictive Markers of Chronic Lung Disease
Background: The aims of this study were to discern the impact of premature lung disease on cardiac development in the first year of life and to determine if quantitative echocardiographic measures of function could predict the severity of chronic lung disease in premature infants.
Methods: 100 premature infants (26 ± 2 weeks at birth) were prospectively enrolled and followed over the first year of life through the Premature and Respiratory Outcomes Program (NIH 1U01 HL1014650). Ventricular systolic function was assessed using myocardial strain. Measurements of right (RV) and left (LV) ventricular strain were acquired and compared at 5 time points: day of life one and three (n=30), 32 and 36 weeks post-menstrual age (n=100), and 1 year corrected age (n=50). The primary outcome was bronchopulmonary dysplasia (BPD), as defined by the 2001 NIH Workshop Criteria and the 2004 Physiological Definition. Infants were grouped and compared by the development and severity of BPD at 36 weeks PMA (no/mild vs. moderate/severe and yes vs. no BPD).
Results: RV strain increases over the first year of life, while LV strain remains relatively unchanged from birth to one year (Fig 1). 50 infants developed moderate/severe BPD. At 32 weeks PMA, RV strain was significantly lower in the infants with mod/severe BPD (-17.5 ± 4% vs. -20.2 ± 3%, p=0.004). RV strain at 32 weeks decreased (p=0.009) with increasing severity of BPD (Fig 2). At 1 year of life there was no differences between the groups (RV strain: -24.2 ± 3 vs. -23.8 ± 2, p=0.45).
Conclusion: RV strain increases with maturation, reflecting physiological changes in postnatal loading conditions. LV function remains persevered with maturation, regardless of BPD severity. Infants who develop BPD have decreased RV function at 32 weeks PMA. This delay in maturation in RV function at 32 and 36 weeks PMA appears to recover by one year of life. Decreased RV strain, as early as 32 weeks PMA, may identify premature infants with a maladapted RV-pulmonary vascular axis.
Author Disclosures: P.T. Levy: None.
- © 2014 by American Heart Association, Inc.