Maternal cardiac evaluation during uncomplicated twin pregnancy with emphasis on the diastolic function

The objective of the study was to evaluate the longitudinal changes in maternal systolic and diastolic function in a series of women carrying an uncomplicated twin pregnancy.

A series of women carrying a twin pregnancy underwent standard M-mode, 2-dimensional color Doppler, and tissue Doppler transthoracic echocardiography during the first (11-13 weeks), the second (20-23 weeks), the third (28-32 weeks) trimesters, and the postpartum (6 months after delivery).

From January 2012 to September 2013, 30 women with an uncomplicated twin pregnancy were included in this prospective study. All the pregnancies were diamniotic including 24 dichorionic and 6 monochorionic sets. Overall, 60 live births were observed with a mean gestational age at delivery of 37 ± 1 weeks and a mean birthweight of 2532 ± 313 g. During pregnancy a significant worsening of left ventricle systolic function expressed by ejection fraction, fractional shortening and S1 longitudinal contractility decrease was observed. These findings also persisted at postpartum assessment. Regarding diastolic function, our data showed a significant progressive reduction of pulsed Doppler E-wave velocity and an increase of A-wave from the first to the third trimester. Similar changes were documented for tissue Doppler E1 and A1 peak velocities assessed at the level of the mitral and tricuspid annulus. After delivery diastolic findings returned to values comparable with those obtained in the first trimester.

In uncomplicated twin gestations, significant changes in maternal systolic and diastolic function occur from the first to the third trimester. Moreover, although diastolic parameters normalize after pregnancy, a relative systolic dysfunction seems to persist after delivery.