The aim of this study was: echocardiographical assessment of cardiac alterations in late-preterm newborns with hypoxic respiratory failure (HRF), and, study serum pentraxin-3 (PTX-3) in relation to the severity of respiratory impairment and to some echocardiographic parameters (i.e. ejection fraction (EF), stroke volume (SV) and cardiac output (CO). We enrolled in this study 40 newborn infants whose 22 (group I) with moderate HRF and 18 (group II) with severe HRF. In group I the mean values of EF, SV and CO were significantly higher than in the group II. Our results showed a significant increase of PTX-3 in group II patients at 24h of life when compared to group I. Taking patients all together (n=40), we found a significant (R=-73) reverse correlation between EF and serum values of PTX-3. PTX-3 in our patients with HRF is affected by the severity of the hypoxic insult and correlate with the cardio-vascular impairment.