Right Ventricular Diastolic Function Measured by Tissue Doppler Imaging Predicts Early Outcome in Congenital Diaphragmatic Hernia

Abstract

To investigate the relationship between early right ventricular function measured by tissue Doppler imaging and early outcome measures in newborn infants with congenital diaphragmatic hernia. Retrospective cohort study. Surgical neonatal ICU within a regional pediatric center. Twenty newborn infants with congenital diaphragmatic hernia. None. Analysis of serial echocardiograms in a cohort of 20 infants with congenital diaphragmatic hernia was done. Tissue Doppler early diastolic and systolic myocardial velocities were measured to assess diastolic and systolic function, respectively, in the basal right ventricle. Pulmonary:systemic peak pressure ratio was estimated using velocity of tricuspid regurgitation. Physiologic, treatment, and early outcome data (duration of respiratory support and length of stay) were recorded. For analysis, duration of respiratory support was selected as the main outcome measure, and infants were divided into two groups based on median duration of respiratory support of 21 days: duration of respiratory support more than 21 days and duration of respiratory support less than 21 days. In 16 surviving infants, mean right ventricular early diastolic myocardial velocity on days 1 and 2 of life correlated with length of stay and duration of respiratory support (r = -0.75, p = 0.002 and r = -0.84, p = 0.0001, respectively). Mean pulmonary:systemic peak pressure ratio on days 1 and 2 of life did not significantly correlate with outcome measures. At receiver-operating characteristics analysis, averaged right ventricular early diastolic myocardial velocity on days 1 and 2 of life of less than 4.6 cm/s predicted duration of respiratory support more than 21 days, with 100% sensitivity and 88% specificity (area under the curve = 0.96, p = 0.002). Right ventricular early diastolic myocardial velocity was significantly lower in the first week of life in the duration of respiratory support more than 21-day group on days 1 and 2 and days 7 and 8. After surgery, right ventricular early diastolic myocardial velocity decreased in the duration of respiratory support more than 21-day group and was significantly lower at days 3 and 4 postoperative. Tissue Doppler imaging mean right ventricular early diastolic myocardial velocity on days 1 and 2 of life predicted early outcome in surviving infants with congenital diaphragmatic hernia. Right ventricular diastolic dysfunction is associated with disease severity in congenital diaphragmatic hernia. Right ventricular function may be optimized by delaying surgical repair in infants with severe congenital diaphragmatic hernia.