BACKGROUND

The detailed hemodynamics after patent ductus arteriosus (PDA) ligation in preterm infants remain unknown. We aimed to clarify the effect of surgical ligation on left ventricular (LV) and right ventricular (RV) volume and function.

METHODS

Echocardiography was performed in 41 preterm infants (median gestational age: 25 weeks) before and after PDA ligation. Global longitudinal strain was determined using three-dimensional speckle-tracking echocardiography. These values were compared with those in 36 preterm infants without PDA (non-PDA).

RESULTS

Preoperatively, the PDA group had greater end-diastolic volume (EDV) and cardiac output (CO) in both ventricles, a higher LV ejection fraction (LVEF) (53% vs 44%) and LV global longitudinal strain, and a lower RVEF (47% vs 52%) than the non-PDA group. At 4-8 h postoperatively, the two groups had a similar LVEDV and RVEDV. However, the PDA group had a lower EF and CO in both ventricles than the non-PDA group. At 24-48 h postoperatively, the RVEF was increased, but the LVEF remained decreased, and LVCO was increased.

CONCLUSIONS

PDA induces biventricular loading and functional abnormalities in preterm infants, and they dramatically change after surgery. Three-dimensional echocardiography may be beneficial to understand the status of both ventricles.

IMPACT

Preterm infants are at high risk of hemodynamic compromise following a sudden change in loading conditions after PDA ligation. Three-dimensional echocardiography enables quantitative and serial evaluation of ventricular function and volume in preterm infants with PDA. PDA induces biventricular loading and functional abnormalities in preterm infants, and they dramatically change after surgery.