The aim of this study was to investigate the importance of myocardial performance index as an additive criterion to Sarnat criteria in differential diagnosis of newborn babies with moderate and severe hypoxic–ischaemic encephalopathy.

Our study group included 50 healthy term newborn babies and 20 newborn babies with hypoxic–ischaemic encephalopathy. The 20 newborn babies with hypoxic–ischaemic encephalopathy were scored using Sarnat grades. Left and right ventricular functions were determined on the first day and thereafter in the 1, 3–4, 6–7, and 11–12 months of life by M-Mode and pulsed Doppler.

Myocardial performance indexes of the left ventricle were significantly higher in the severe hypoxic–ischaemic encephalopathy group than in the control group during the first, second, and third analyses (p = 0.01, p = 0.02, p = 0.02, respectively) and only during the first analysis (p = 0.01) in the moderate hypoxic–ischaemic encephalopathy group. In addition, the myocardial performance indexes of the right ventricle were significantly higher during the first, second, and third analyses in both severe and moderate hypoxic–ischaemic encephalopathy groups than in the control group (p = 0.01, all). Hypoxia-induced alterations last longer in the right ventricle than in the left ventricle in the moderate group, as during the second and third analyses myocardial performance index continues to be higher than the control group.

Myocardial performance indexes for the left and right ventricles were significantly higher in both severe and moderate hypoxic–ischaemic encephalopathy groups than in the control group during the first analysis, and myocardial performance index greater than or equal to 0.5 can be used in order to distinguish moderate and severe hypoxic–ischaemic encephalopathy babies according to Sarnat grades as a discriminative additive criterion.