Objective <p>To compare end organ hemodynamic in hemodynamically significant (hs) and non-hemodynamically significant (non-hs) patent ductus arteriosus (PDA).</p> Methods <p>This retrospective study enrolled preterm infants with PDA who were admitted to the neonatal intensive care unit (NICU) of our center between January 2021 and December 2024. According to comprehensive evaluations of echocardiographic findings and clinical parameters, infants were classified into hemodynamically significant PDA (hsPDA) and non-hsPDA groups. Clinical characteristics and bedside Doppler ultrasound measurements of the anterior cerebral artery (ACA), superior mesenteric artery (SMA), and renal artery (RA) were collected to evaluate the effects of different PDA hemodynamic states on organ blood flow.</p> Results <p>A total of 103 preterm infants with PDA were analyzed, including 50 in the hsPDA group and 53 in the non-hsPDA group. There were no significant differences in demographic or clinical variables between the two groups. Compared with the non-hsPDA group, the hsPDA group exhibited lower end-diastolic velocity (EDV) and mean velocity (MV) and higher resistance index (RI) in both the SMA and RA, while parameters of the ACA showed no significant differences. The incidence of necrotizing enterocolitis was higher in the hsPDA group, whereas other complications did not differ significantly between groups.</p> Conclusions <p>Different hemodynamic states of PDA have distinct impacts on organ perfusion in preterm infants. Bedside Doppler ultrasound provides a sensitive tool for early detection of these hemodynamic alterations.</p>