Use of the myocardial performance index as a prognostic indicator of adverse fetal outcome in poorly controlled gestational diabetic pregnancies.

OBJECTIVE

The aim of this study was to determine whether there are any changes in cardiac function in fetuses of poorly controlled gestational diabetics and whether these changes influence perinatal outcome.

METHODS

Twenty-nine pregnant women with severe gestational diabetes on insulin therapy in the third trimester of pregnancy were recruited and matched with 29 women with normal pregnancies (control group). Using Doppler echocardiography, the modified myocardial performance index (Mod-MPI) and E wave/A wave peak velocities (E/A) ratios were determined. Placental resistance Doppler markers were also determined in both groups. Adverse perinatal outcome was defined as perinatal death, admission to the neonatal intensive care unit, cord pH <7.15, 5-min Apgar score <7 and presence of cardiomyopathy.

RESULTS

The median Mod-MPI was increased (0.59 vs 0.38; p < 0.0001) and the E/A ratio was decreased (0.65 vs 0.76; p < 0.0001) in fetuses of diabetic mothers compared with controls. An MPI >0.52 had a sensitivity of 100% [95% confidence interval (CI) 85-100%] and specificity of 92% (95% CI 70-92%) for prediction of adverse perinatal outcome, including one stillbirth and one neonatal death. No abnormal outcomes occurred in the control group.

CONCLUSIONS

There is significant impairment of cardiac function in fetuses of poorly controlled gestational diabetics. Mod-MPI and E/A ratio have the potential to improve fetal surveillance in diabetic pregnancies.