Hemodynamic evaluation following ductal closure and association with IVH in premature infants born at 22-23weeks gestation.

Background: Intraventricular hemorrhage (IVH) remains a major complication in extremely preterm infants, but the immediate hemodynamic changes associated with hemorrhage after ductal closure are not well defined. Methods: This was a two-center retrospective cohort study conducted at two tertiary neonatal intensive care units. Hemodynamic parameters, including left ventricular diastolic diameter, mean velocity of circumferential fiber shortening, end-systolic wall stress, mean arterial pressure, heart rate, and internal cerebral vein waveform grade, were assessed serially from birth to 72 h of life. Generalized linear mixed-effects models were used to evaluate temporal associations between post-closure hemodynamic changes and IVH. Results: In this two-center retrospective cohort study, 26 infants born at 22-23 weeks' gestation were included. Seven infants developed grade 2-4 IVH, all first detected after PDA closure, while 19 who did not IVH. Infants who developed IVH showed a distinct post-closure pattern characterized by increased end-systolic wall stress, mean arterial pressure, and heart rate, together with reduced mean velocity of circumferential fiber shortening, within 12 h after ductal closure. Between-group differences were significant at 6 and 12 h after closure (all Conclusion: Hemodynamic instability emerging within 12 h after ductal closure was associated with subsequent IVH in infants born at 22-23 weeks' gestation. These findings identify the immediate post-closure period as a critical window for circulatory monitoring and potential targeted intervention.