Relationship Between Postnatal Pulmonary Arterial Pressure and Altered Diastolic Function in Neonates with Down Syndrome.

ABSTRACT

OBJECTIVE: To assess the influence of diastolic dysfunction on the evolution of pulmonary hypertension in neonates with Down Syndrome over the early newborn period. STUDY DESIGN: This was a prospective observational cohort study. Echocardiography was performed three times over the first week of life in both Down syndrome and control cohorts. Measurements of pulmonary arterial pressure in addition to left ventricular (LV) and right ventricular systolic and diastolic function were collected. RESULTS: Seventy babies with Down syndrome and 60 control infants were enrolled. Forty-eight of the infants with Down syndrome (69%) were born with congenital heart disease (CHD). Echocardiography surrogates of pulmonary hypertension and myocardial function remained significantly impaired in the Down syndrome group in comparison with control infants (all P < .01). In the Down syndrome group, LV early diastolic strain rate was independently associated with measures of pulmonary hypertension while controlling for gestational age, cesarean delivery, and the presence of CHD (P < .01). CONCLUSIONS: Intrinsic LV diastolic impairment is directly associated with higher indices of pulmonary hypertension in infants with Down syndrome and may be a contributing factor to its evolution.