Abstract 16681: Early Left Ventricular Dysfunction in Healthy Young Adults Born Premature

Rationale: Preterm birth, or less than 37 weeks completed gestation, affects one in 10 live births in the United States. Moderate to extreme premature birth, or less than 32 weeks gestation, is associated with up to a 17-fold increased risk for the development of heart failure in adolescents and young adults. Here, we sought to characterize left ventricular (LV) function in young adults born premature. Methods: Adults born preterm (n=11; gestational age 28.2±0.8 weeks; current age 27±1 years) were recruited from the Newborn Lung Project at the University of Wisconsin-Madison, a prospective cohort of infants born 1988-1991 with birth weight <1500 g. Controls were recruited from the general population (n=12; age 26±1 years). All subjects were free from adult cardiopulmonary disease. Subjects underwent cardiac magnetic resonance imaging (MRI) on a 3.0T scanner. Measures included standard assessment of LV function and LV strain. 4D flow imaging was acquired with a radially-undersampled PC VIPR sequence to assess systolic and diastolic LV kinetic energy, and corresponding LV energetic efficiency was defined as stroke volume normalized by the systolic and diastolic kinetic energy . Mann-Whitney tests were performed to assess for statistical significance (p<0.05). Results: Young adults born premature had significantly smaller chamber volumes, even when indexed to body size (table 1). However, stroke volume was maintained due to a higher ejection fraction. Cardiac output and index were significantly higher in young adults born premature, due to a higher resting heart rate. Strain analysis confirmed a hyperdynamic LV. 4D flow demonstrated a significantly higher LV energy cost, resulting in an energetically inefficient LV. Conclusions: Otherwise healthy young adults born premature demonstrate a hypercontractile, energetically inefficient LV, which may provide mechanistic insight into the increased risk for heart failure in this high-risk population.