Quantification of Myocardial Work by 2-D Echocardiography during a Normal Pregnancy: A Preliminary Study

This study was aimed at investigating the adaptive changes in myocardial work (MyW) during normal pregnancy. Sequential 2D standard and speckle-tracking echocardiography was performed on 41 pregnant women in each gestational trimester and 4 to 11 mo after delivery. Thirty-eight age-matched, healthy, non-pregnant women served as controls. Four components of MyW—global myocardial work index (GWI), constructive work (GCW), wasted work (GWW) and work efficiency (GWE)—were calculated. GWI began to decline early in the first trimester and remained at a low level until delivery; GCW gradually decreased with gestational progression and reached its lowest level in the third trimester. When compared with the values for non-pregnant women and those postpartum, GWE and GWW remained unchanged in gestation. This study provides normal ranges of MyW during pregnancy. Despite the adapted decrease in GWI and GCW, the myocardium manages to work efficiently in the healthy pregnancy with drastic hemodynamic alternations.